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1)Yes,Since design 1 generates 744 kg/hr while design 2 generates 203 kg/hr
No, Since the value for Design 1 in normal phase is 218 while for Design 2 it is 6,so it is not even in the range of 5%
No,Since the increase in emission level in Design 2 in normal phase is 3 while in Design 1 it is 13 so it is not in the 25% range, because 25% would be around 10.


2)Only statement 1 is Yes,since the cost is less for Design 1 but it will generate more solid waste and more pollutant than that by Design 2


3)A,since in design 1 the emission per hour during startup is 744,while in design 2 it is 203,so per the question the time is 1 hour for Type A,so time for Type B, considering equal emission is:

744*1= 203*x*3

x=1.22

Thanks for pointing out the important case

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Even I think Question answer should be A.
203(x) = 744
Where X is the no. Of hours for which it's emitting same level of pollutants.
And the result is near about 3.66

Kindly confirm OA SajjadAhmad

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Please refer to the pic uploaded.

Question no. 1 YES NO NO,
Question no. 2 YES NO NO,
Question no. 3 IMO its 2.22 hrs,
It is little confusing, please clarify.



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Official Explanation

3. Suppose that the startup phase for Type A generators takes exactly one hour. Given this and based on the information in the tabs, which one of the following would be closest to the startup time, in hours, for Type B generators that would result in equal emissions of Pollutant Y for both power plant designs during a single startup phase?

Explanation

Let \(t\) denote the number of hours of startup it will take for the amount of Pollutant \(Y\) emitted by Design 2 to equal the amount emitted by Design 1 in a single hour of startup. Design 1 uses one Type \(A\) generator, which the chart shows emits 744 kg of Pollutant \(Y\) in an hour of startup. Design 2 uses three Type B generators, each of which emits 203 kg of Pollutant Y per hour of startup. Thus, since t hours of Design 2 startup emits the same amount of Pollutant Y as one hour of Design 1 startup, 3(203 kg/hr)(t hr) = 744 kg. Solving for t gives \(t = \frac{744}{609}\), which is approximately 1.22.

The correct answer is 1.22.
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SajjadAhmad
Official Explanation

3. Suppose that the startup phase for Type A generators takes exactly one hour. Given this and based on the information in the tabs, which one of the following would be closest to the startup time, in hours, for Type B generators that would result in equal emissions of Pollutant Y for both power plant designs during a single startup phase?

Explanation

Let \(t\) denote the number of hours of startup it will take for the amount of Pollutant \(Y\) emitted by Design 2 to equal the amount emitted by Design 1 in a single hour of startup. Design 1 uses one Type \(A\) generator, which the chart shows emits 744 kg of Pollutant \(Y\) in an hour of startup. Design 2 uses three Type B generators, each of which emits 203 kg of Pollutant Y per hour of startup. Thus, since t hours of Design 2 startup emits the same amount of Pollutant Y as one hour of Design 1 startup, 3(203 kg/hr)(t hr) = 744 kg. Solving for t gives \(t = \frac{744}{609}\), which is approximately 1.22.

The correct answer is 1.22.


In the question it is written that--
result in equal emissions of Pollutant Y for both power plant designs

SajjadAhmad please explain sir whether I'm making a wrong assumption of the highlighted part.
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1.1
1. Yes
2. No
3. No

1.2
1. Yes
2. No
3. Yes

1.3
Answer: A. 3.67

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1.1
Yes --- Type A generators cost less than Type B generators to fuel per unit of power generated
No --- Type A generators produce solid waste that is difficult and expensive to dispose of safely.
No --- Type B generators produce no solid waste and, as compared to Type A generators, vent approximately half as
much Pollutant X, and even less Pollutant Y, per unit of power generated annually.

1.2 ( from table)
Yes --- A ( 744 x 1 ) B ( 203 x 3 )
No --- Type 1- 218 therefore 5 % = 10.9 , type 2 - 3 x 6 = 18
No --- Type 1 - 13 , Type 2 - 3 X 3 = 9 is more that 25 % of type 1

1.3 - D 1.22
During startup = emission by Type A in 1 hr = 744 kg
During stratup of 2 - 3 no of type B generator = 3 * 203 kg /hr
Hence no of hours type 2 should run to emit same quantity of Y emissions from type 1 ( 1 no A ) = 744 / ( 3* 203) = 1.22
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1.1 Suppose that the utility chooses Design 1 over Design 2. For each of the following motivations, select Yes if the information in the tabs suggests that it would help explain this choice. Otherwise, select No.

A desire to use the type of generator that costs less to fuel per unit of power generated.....YES (Since design 1 uses type A generator & design 2 uses type B generator, Cost of type A generator is less than that of type B)
A desire to avoid having to dispose of solid waste.........No (Since design 1 uses type A generator & design 2 uses type B generator, type A generator produce more solid waste, where as type B does not produce any solid waste)
A desire to emit less Pollutant X per unit of power generated annually......No (Since design 1 uses type A generator & design 2 uses type B generator, type A generator vents double Pollutant X than do type B)


1.2 For each of the following statements, select Yes if the statement accurately reflects the information given in the tabs. Otherwise, select No.

During the startup phase, the Design 1 power plant would emit more Pollutant Y per hour than would the Design 2 power plant......Yes (Design 1= 744, Design 2 = 203*3=609)
During the normal generating phase, the emissions per hour of Pollutant Y from the Design 2 power plant would be less than 5% of those from the Design 1 power plant......NO (Design 1 = 218, 5% = 10.90, Design 2 = 18)
During the normal generating phase, the contribution to the ground-level concentration of Pollutant Y from the Design 2 power plant would be less than 25% of that from the Design 1 power plant......No (Design 1 = 13, 25%=3.25; Design 2= 3*3=9)

1.3 Suppose that the startup phase for Type A generators takes exactly one hour. Given this and based on the information in the tabs, which one of the following would be closest to the startup time, in hours, for Type B generators that would result in equal emissions of Pollutant Y for both power plant designs during a single startup phase?

In 1 hour Type A will emit - 744
In 1 hour Type B will emit - 609 (since 3 of such kind will be required)

Difference = 135 for 3 type B generators, 1 generator will need to produce extra 45 to match the emission of Type A.
(45*60)/203 (calculating extra start up time in minutes) = 13.5 minutes = .22 hour

So total time needed for type b generators to start, so as to emit the same amount of emissions as that of type a generator, will be 1 hour 13.5 minutes / 1.22 hours.

IMO Option D
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1.1 Suppose that the utility chooses Design 1 over Design 2. For each of the following motivations, select Yes if the information in the tabs suggests that it would help explain this choice. Otherwise, select No.

Yes No

A desire to use the type of generator that costs less to fuel per unit of power generated - Yes-ANSWER
A desire to avoid having to dispose of solid waste- No- ANSWER
A desire to emit less Pollutant X per unit of power generated annually - No- ANSWER


1.2 For each of the following statements, select Yes if the statement accurately reflects the information given in the tabs. Otherwise, select No.

Yes............ No........
During the startup phase, the Design 1 power plant would emit more Pollutant Y per hour than would the Design 2 power plant. Yes - ANSWER
During the normal generating phase, the emissions per hour of Pollutant Y from the Design 2 power plant would be less than 5% of those from the Design 1 power plant. Yes - ANSWER
During the normal generating phase, the contribution to the ground-level concentration of Pollutant Y from the Design 2 power plant would be less than 25% of that from the Design 1 power plant. Yes-ANSWER


1.3 Suppose that the startup phase for Type A generators takes exactly one hour. Given this and based on the information in the tabs, which one of the following would be closest to the startup time, in hours, for Type B generators that would result in equal emissions of Pollutant Y for both power plant designs during a single startup phase?

A. 3.67
B. 0.27
C. 0.81
D. 1.22
E. 36.33

answer is A 3.67
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DESIGN ( same amount of power annually)
D1: 1 PG A
D2: 3 PG B

A vs B
Costs: A < B
Pollutant : B (X, Y)<A (though better but B wins)
Chimney : A>B
Solid pollutant : A>B (nil)

POLLUTANTS
Y : A and B emit Y that can be concentrated near ground. A> B

1.1 Suppose that the utility chooses Design 1 over Design 2. For each of the following motivations, select Yes if the information in the tabs suggests that it would help explain this choice. Otherwise, select No
-A desire to use the type of generator that costs less to fuel per unit of power generated
NO, All we know that Cost of A < B per unit. But, we don't know which costs more 1 A (in Design 1) or 3 B (in Design 2).
-A desire to avoid having to dispose of solid waste
YES, Type B generators produce no solid waste while A does. Hence Design 2 is better in this aspect.
-A desire to emit less Pollutant X per unit of power generated annually
YES
As compared to Type A generators, Type B vent approximately half as much Pollutant X. However, Design 2 needs 3 Type B generators . Hence total Pollutant X by B is 0.5 x 3 = 1.5 times of Type A


1.2 For each of the following statements, select Yes if the statement accurately reflects the information given in the tabs. Otherwise, select No.
-During the startup phase, the Design 1 power plant would emit more Pollutant Y per hour than would the Design 2 power plant.
YES, during startup,Design 1 emits (per hour) Y 744 kg, Design B emits Y = 3 x 203 = 606 kg
-During the normal generating phase, the emissions per hour of Pollutant Y from the Design 2 power plant would be less than 5% of those from the Design 1 power plant.
NO, during normal phase, , Design 1 emits (per hour) Y = 218 Kg, Design 2 emits (per hour) Y = 3x 6 = 18 Kg (this is greater than 5% of those from Design 1)
-During the normal generating phase, the contribution to the ground-level concentration of Pollutant Y from the Design 2 power plant would be less than 25% of that from the Design 1 power plant.
During normal phase, ground-level concentration of Pollutant Y
Design 2 : 3 x B's contribution = 3 x 3 mcg/m3 = 9 mcg/m3
Design 1 : 13 mcg/m3
9 is greater than 25% of 13.
Hence NO.


1.3 Suppose that the startup phase for Type A generators takes exactly one hour. Given this and based on the information in the tabs, which one of the following would be closest to the startup time, in hours, for Type B generators that would result in equal emissions of Pollutant Y for both power plant designs during a single startup phase?
Type A takes 1 hour to start up . Hence Pollutant Y emitted = 744 Kg
Hence mba (has only one Type A gen) emits 744 Kg of Y during start up.
For equal emissions of Pollutant Y for both power plant designs D1 and D2,
Each of Type B generators emit = 744 kg/ Number of Type B in Design 2 = 744/3= 248Kg
Time taken by each of Type B (in hours) = 248 kg/203kg/hr = 1.22 hrs.

Hence D.
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Hi all

Competition mode is off now for this question and OAs are posted.

Question 1.1

Yes, No and No

Question 1.2

Yes, No and No

Question 1.3

D

rocky620 and pemathew have done a good job here rest are OK. Let me know if need the explanation.

Good Luck
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Sajjad1994 - i had a doubt in this question we are saying 1 Generator A used in design 1 and 3 generators used in Design 2 . But if we see q1 where its asked cost per unit of power to fuel we are not considering 3 generators in design 2 . Also when we are asked about emissions we choose not to consider 3 generators while checking for answer .

While from q2 and q3 onwards we consider 3 generators working in design b .

wanted some clarification on this as if you consider the both generators generate same power anually - we cannot be sure about 3 generators working together to generate same level of output , may be somebody can assume that in type b generators there is some heating issue due to which generators have to work in a cyclic manner and not 1 at a time . Request u to pls clarify on this particular part of assumption on type b generators working together to generate same power . In that case answers to q1 -part1 and part3 should also be taken as per 3 generators of type B
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Got it Sajjad

But I still think this question can be disputed
If genset a and b are of same power and it’s just that in design 2 gensets are operated cyclically , not all together due to some overheating issue .

But if genset b are operated together and have different lower power than A than the answers given in OA hold true.

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Hlw sir,
In qustion no 1.3 how did you inferred 3 type b generators.
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Sajjad1994
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Sajjad1994 - i had a doubt in this question we are saying 1 Generator A used in design 1 and 3 generators used in Design 2 . But if we see q1 where its asked cost per unit of power to fuel we are not considering 3 generators in design 2 . Also when we are asked about emissions we choose not to consider 3 generators while checking for answer .

While from q2 and q3 onwards we consider 3 generators working in design b .

wanted some clarification on this as if you consider the both generators generate same power anually - we cannot be sure about 3 generators working together to generate same level of output , may be somebody can assume that in type b generators there is some heating issue due to which generators have to work in a cyclic manner and not 1 at a time . Request u to pls clarify on this particular part of assumption on type b generators working together to generate same power . In that case answers to q1 -part1 and part3 should also be taken as per 3 generators of type B
Hello Deepak

This question belongs to GMAT Prep so there is no doubt on the quality of the questions, Please read the OE below.

Official Explanation

1.1 Suppose that the utility chooses Design 1 over Design 2. For each of the following motivations, select Yes if the information in the tabs suggests that it would help explain this choice. Otherwise, select No.

RO1

Design 1 uses a single Type A generator. The discussion says that Type A generators cost less than Type B generators to fuel per unit of power generated, so a desire to use a Type A generator would help explain the choice of Design 1.

The correct answer is Yes.

RO2

The discussion says that Type A generators used in Design 1 produce solid waste, unlike the Type B generators used in Design 2. Thus, a desire to avoid having to dispose of solid waste would not help explain the choice of Design 1.

The correct answer is No.

RO3

Designs 1 and 2 generate the same amount of power per year. However, the generators used in Design 2 vent about half as much Pollutant X per unit of power generated annually as the generators used in Design 1. Therefore, the total amount of Pollutant X vented per year from the use of Design 2 is about half of the total amount of Pollutant X vented per year from the use of Design 1. Because both designs generate the same amount of power per year, this same relationship holds for the amount of Pollutant X vented per unit of power generated annually. Thus, a desire to emit less Pollutant X per unit of power generated annually would be an argument for choosing Design 2 over Design 1 and not an argument for choosing Design 1 over Design 2.

The correct answer is No.

1.2 For each of the following statements, select Yes if the statement accurately reflects the information given in the tabs. Otherwise, select No.

RO1

According to the discussion, Design 1 would use a single Type A power generator. The chart shows that a Type A generator emits 744 kg/hr of Pollutant Y during the startup phase. The discussion indicates that Design 2 would use three Type B power generators. The chart shows that each Type B generator emits 203 kg/hr of Pollutant Y during the startup phase. The total emission rate for three Type B generators would be 3(203) = 609 kg/hr. Since 744 > 609, Design 1 would emit more Pollutant Y per hour during the startup phase than would Design 2.

The correct answer is Yes.

RO2

The chart shows that during the normal generating phase, a Type B generator emits 6 kg/hr of Pollutant Y. Design 2 uses three of these generators, so its total emission rate during this phase would be 3(6) = 18 kg/hr. Design 1 uses a single Type A generator, which the chart shows emits 218 kg/hr of Pollutant Y during the normal generating phase. Five percent of 218 kg/hr is 10.9 kg/hr, and the emission rate of Design 2 (18 kg/hr) is not less than this amount.

The correct answer is No.

RO3

According to the chart, each Type B generator increases the ground-level concentration of Pollutant Y by 3 mcg/m3 during the normal generating phase. Design 2 uses three of these generators, so its total contribution would be 3(3) = 9 mcg/m3. Design 1 uses a single Type A generator, which the chart shows to increase the ground-level concentration of Pollutant Y by 13 mcg/m3 during the normal generating phase. Twenty-five percent of 13 is 3.25, and the Pollutant Y contribution of Design 2 (9 mcg/m3) is not less than that number.

The correct answer is No.

1.3 Suppose that the startup phase for Type A generators takes exactly one hour. Given this and based on the information in the tabs, which one of the following would be closest to the startup time, in hours, for Type B generators that would result in equal emissions of Pollutant Y for both power plant designs during a single startup phase?

Let t denote the number of hours of startup it will take for the amount of Pollutant Y emitted by Design 2 to equal the amount emitted by Design 1 in a single hour of startup. Design 1 uses one Type A generator, which the chart shows emits 744 kg of Pollutant Y in an hour of startup. Design 2 uses three Type B generators, each of which emits 203 kg of Pollutant Y per hour of startup. Thus, since t hours of Design 2 startup emits the same amount of Pollutant Y as one hour of Design 1 startup, 3(203 kg/hr)(t hr) = 744 kg. Solving for t gives \(t=\frac{744}{609}\), which is approximately 1.22.

The correct answer is 1.22.

Hope it help.
­1.1 Suppose that the utility chooses Design 1 over Design 2. For each of the following motivations, select Yes if the information in the tabs suggests that it would help explain this choice. Otherwise, select No.

RO3

Designs 1 and 2 generate the same amount of power per year. However, the generators used in Design 2 vent about half as much Pollutant X per unit of power generated annually as the generators used in Design 1. Therefore, the total amount of Pollutant X vented per year from the use of Design 2 is about half of the total amount of Pollutant X vented per year from the use of Design 1. Because both designs generate the same amount of power per year, this same relationship holds for the amount of Pollutant X vented per unit of power generated annually. Thus, a desire to emit less Pollutant X per unit of power generated annually would be an argument for choosing Design 2 over Design 1 and not an argument for choosing Design 1 over Design 2.

I think the answer to this one is Yes. Since design 1 uses 1 Type A generator while design 2 uses 3 Type B generator, each of which vent about half as much Pollutant X. So Design 2 vents out 3 x 0.5 Design 1 (Type A) = 1.5 times mba.
Am i missing out on something Sajjad1994 ?
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Sajjad1994
Deepakjhamb
Sajjad1994 - i had a doubt in this question we are saying 1 Generator A used in design 1 and 3 generators used in Design 2 . But if we see q1 where its asked cost per unit of power to fuel we are not considering 3 generators in design 2 . Also when we are asked about emissions we choose not to consider 3 generators while checking for answer .

While from q2 and q3 onwards we consider 3 generators working in design b .

wanted some clarification on this as if you consider the both generators generate same power anually - we cannot be sure about 3 generators working together to generate same level of output , may be somebody can assume that in type b generators there is some heating issue due to which generators have to work in a cyclic manner and not 1 at a time . Request u to pls clarify on this particular part of assumption on type b generators working together to generate same power . In that case answers to q1 -part1 and part3 should also be taken as per 3 generators of type B
Hello Deepak

This question belongs to GMAT Prep so there is no doubt on the quality of the questions, Please read the OE below.

Official Explanation

1.1 Suppose that the utility chooses Design 1 over Design 2. For each of the following motivations, select Yes if the information in the tabs suggests that it would help explain this choice. Otherwise, select No.

RO1

Design 1 uses a single Type A generator. The discussion says that Type A generators cost less than Type B generators to fuel per unit of power generated, so a desire to use a Type A generator would help explain the choice of Design 1.

The correct answer is Yes.

RO2

The discussion says that Type A generators used in Design 1 produce solid waste, unlike the Type B generators used in Design 2. Thus, a desire to avoid having to dispose of solid waste would not help explain the choice of Design 1.

The correct answer is No.

RO3

Designs 1 and 2 generate the same amount of power per year. However, the generators used in Design 2 vent about half as much Pollutant X per unit of power generated annually as the generators used in Design 1. Therefore, the total amount of Pollutant X vented per year from the use of Design 2 is about half of the total amount of Pollutant X vented per year from the use of Design 1. Because both designs generate the same amount of power per year, this same relationship holds for the amount of Pollutant X vented per unit of power generated annually. Thus, a desire to emit less Pollutant X per unit of power generated annually would be an argument for choosing Design 2 over Design 1 and not an argument for choosing Design 1 over Design 2.

The correct answer is No.

1.2 For each of the following statements, select Yes if the statement accurately reflects the information given in the tabs. Otherwise, select No.

RO1

According to the discussion, Design 1 would use a single Type A power generator. The chart shows that a Type A generator emits 744 kg/hr of Pollutant Y during the startup phase. The discussion indicates that Design 2 would use three Type B power generators. The chart shows that each Type B generator emits 203 kg/hr of Pollutant Y during the startup phase. The total emission rate for three Type B generators would be 3(203) = 609 kg/hr. Since 744 > 609, Design 1 would emit more Pollutant Y per hour during the startup phase than would Design 2.

The correct answer is Yes.

RO2

The chart shows that during the normal generating phase, a Type B generator emits 6 kg/hr of Pollutant Y. Design 2 uses three of these generators, so its total emission rate during this phase would be 3(6) = 18 kg/hr. Design 1 uses a single Type A generator, which the chart shows emits 218 kg/hr of Pollutant Y during the normal generating phase. Five percent of 218 kg/hr is 10.9 kg/hr, and the emission rate of Design 2 (18 kg/hr) is not less than this amount.

The correct answer is No.

RO3

According to the chart, each Type B generator increases the ground-level concentration of Pollutant Y by 3 mcg/m3 during the normal generating phase. Design 2 uses three of these generators, so its total contribution would be 3(3) = 9 mcg/m3. Design 1 uses a single Type A generator, which the chart shows to increase the ground-level concentration of Pollutant Y by 13 mcg/m3 during the normal generating phase. Twenty-five percent of 13 is 3.25, and the Pollutant Y contribution of Design 2 (9 mcg/m3) is not less than that number.

The correct answer is No.

1.3 Suppose that the startup phase for Type A generators takes exactly one hour. Given this and based on the information in the tabs, which one of the following would be closest to the startup time, in hours, for Type B generators that would result in equal emissions of Pollutant Y for both power plant designs during a single startup phase?

Let t denote the number of hours of startup it will take for the amount of Pollutant Y emitted by Design 2 to equal the amount emitted by Design 1 in a single hour of startup. Design 1 uses one Type A generator, which the chart shows emits 744 kg of Pollutant Y in an hour of startup. Design 2 uses three Type B generators, each of which emits 203 kg of Pollutant Y per hour of startup. Thus, since t hours of Design 2 startup emits the same amount of Pollutant Y as one hour of Design 1 startup, 3(203 kg/hr)(t hr) = 744 kg. Solving for t gives \(t=\frac{744}{609}\), which is approximately 1.22.

The correct answer is 1.22.

Hope it help.
­1.1 Suppose that the utility chooses Design 1 over Design 2. For each of the following motivations, select Yes if the information in the tabs suggests that it would help explain this choice. Otherwise, select No.

RO3

Designs 1 and 2 generate the same amount of power per year. However, the generators used in Design 2 vent about half as much Pollutant X per unit of power generated annually as the generators used in Design 1. Therefore, the total amount of Pollutant X vented per year from the use of Design 2 is about half of the total amount of Pollutant X vented per year from the use of Design 1. Because both designs generate the same amount of power per year, this same relationship holds for the amount of Pollutant X vented per unit of power generated annually. Thus, a desire to emit less Pollutant X per unit of power generated annually would be an argument for choosing Design 2 over Design 1 and not an argument for choosing Design 1 over Design 2.

I think the answer to this one is Yes. Since design 1 uses 1 Type A generator while design 2 uses 3 Type B generator, each of which vent about half as much Pollutant X. So Design 2 vents out 3 x 0.5 Design 1 (Type A) = 1.5 times mba.
Am i missing out on something Sajjad1994 ?
­
OAs are correct; please refer to the explanation posted here in the link below:

https://gmatclub.com/forum/a-certain-el ... l#p2696724

Thank you!
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Sajjad1994

A certain electric utility is considering exactly two designs (Designs 1 and 2) for a new power generation plant. Each design would result in a plant that would generate the same amount of power annually; but Design 1 would use a single Type A power generator, whereas Design 2 would use three Type B power generators.

Type A generators cost less than Type B generators to fuel per unit of power generated and vent through taller chimneys, which better prevent pollutants from concentrating near the plant. However, Type A generators produce solid waste that is difficult and expensive to dispose of safely.

Type B generators produce no solid waste and, as compared to Type A generators, vent approximately half as much Pollutant X, and even less Pollutant Y, per unit of power generated annually. However, Type B generators vent through much shorter chimneys.
Attachment:
123.jpg

Features:

Design 1:
1 generator of Type A ­;
Less fuel cost per unit of power generated ;
Solid Waste produced which needs to be disposed off ;
Tall chimneys so less pollution near the generator area;
More X and Y pollutants for same power generated

Design 2:
3 generators of Type B ;
More fuel cost per unit of power generated ;
No solid waste so no hassle of disposing it off ;
Short chimneys so more pollution near the generator area ;
Less than half X and Y pollutants for same power generated


Question 1.

1. Suppose that the utility chooses Design 1 over Design 2. For each of the following motivations, select Yes if the information in the tabs suggests that it would help explain this choice. Otherwise, select No


If design 1 was chosen, then it was because they liked certain features of design 1. So for each desire below select Yes if that was one of the reasons why design 1 was chosen.



- A desire to use the type of generator that costs less to fuel per unit of power generated

YES. Design 1 does have lower cost of fuel. So this could have been a reason why design 1 was chosen.


- A desire to avoid having to dispose of solid waste

NO. Design 1 produces solid waste. So this could not have been the reason design 1 was chosen. If this were a desire, then design 2 would have been chosen. It doesn't explain why design 1 was chosen.


- A desire to emit less Pollutant X per unit of power generated annually

NO. Design 1 produces more Pollutant X per unit of power generated annually­. If this were a desire, then design 2 would have been chosen. It doesn't explain why design 1 was chosen.
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