Vehicle exhaust produces dangerously high ozone levels in our city in

Question

Mayor: Vehicle exhaust produces dangerously high ozone levels in our city in hot, humid weather. As an incentive for people to commute by bus rather than by car, special free commuter buses will be scheduled on hot, humid days. Since a bus can carry about 40 people but produces only about 20 times as much exhaust as a car, ozone levels will be lower as long as the buses are more than half full.

Which of the following, if true, most seriously weakens the argument?

A. Most of the people who would take the special free buses are currently members of carpools.
B. The city does not currently have enough buses to transport all of the commuters who normally commute by car. 
C. Buses that would be operating on hot, humid days would rarely, if ever, be filled to capacity.
D. The amount of vehicle exhaust produced in the city is not significantly higher on hot, humid days. 
E. Not all commuter routes are used by enough people to warrant providing bus service for them.

pintukr · Answer

Mayor: Vehicle exhaust produces dangerously high ozone levels in our city in hot, humid weather. As an incentive for people to commute by bus rather than by car, special free commuter buses will be scheduled on hot, humid days. Since a bus can carry about 40 people but produces only about 20 times as much exhaust as a car, ozone levels will be lower as long as the buses are more than half full.

Which of the following, if true, most seriously weakens the argument?

Pre-thinking. The argument's conclusion relies on the reasoning that ozone levels will be lower if the occupancy in buses is greater than 50% (ie, >20 out of 40). The conclusion would be weakened if we are able to prove that despite the occupancy levels in excess of 20, the ozone levels may not get lower.

A. Most of the people who would take the special free buses are currently members of carpools.
 ' Most' , NOT all. A carpool will have 2 occupants at a minimum. So, if they are already member of carpools, they're already producing less exhausts. Hence, weakens the argument that 50% occupation levels will reduce the ozone levels with certainty .

B. The city does not currently have enough buses to transport all of the commuters who normally commute by car.
 Even if a 'significant' people adopt buses, the ozone levels will be reduced. Hence, NOT a weakener.

C. Buses that would be operating on hot, humid days would rarely, if ever, be filled to capacity.
 Even if 50 % 'occupied. it will lower the ozone levels. Occupancy levels to (full) is not required necessarily to realise the lower ozone levels.

D. The amount of vehicle exhaust produced in the city is not significantly higher on hot, humid days.
 Lower exhausts on hot, humid days may not require adoption of buses to realise lower ozone levels. Hence, NOT a weakener.

E. Not all commuter routes are used by enough people to warrant providing bus service for them.
 'Out of scope' option since no link with occupancy levels in the buses for this prompt.

Hence, (A) should be the answer.

BodhiChatterjee · Answer

Answer should be C

A- we don't have any info about carpools

B- We have no information on the number of bus or car users

C- It would have a significant effect only if enough people actually use the buses. If buses continue to run empty and people continue to use cars, it would be useless.

D- Again, no info on the amount of exhaust

E- No info on the commuter routes

Posted from my mobile device

Maria240895chile · Answer

by POE should be A.
I was between A and C.

C talks about full capacity, but the passage stated that just half capacity is enough to make a change.

A is the one that undermines the passage. imagine that X is pollution of a car and pollution from a bus is *20, so 20x. In a bus we need at least 20 to contrast pollution according to the passage. So per person the pollution is 20x/20=X.
A car is made for 1 to 5 people, but because option A talks about a carpool it should be at least 2 persons. Then pollution per people is maximum x/2. So people is producing less pollution using carpooling than changing to buses at 50% capacity. 
So this undermines the argument.

Niayesh99 · Answer

The mayor's argument logic is:  Since a bus can carry about 40 people, but the exhaust gas produced is only about 20 times that of a car, as long as the number of passengers on the bus exceeds half, the ozone level will decrease. This is a very simple division.

A: Most of the people who take the free car are carpoolers. This argument breaks the mayor's premise, that is, the number of passengers on the bus is originally two or three people per car.  Therefore, to reduce the ozone level, it must be greatly more than half.   In fact, if everyone shares a car with three people, the final result is that the bus is not as environmentally friendly as a private car.  A is the correct answer.

B: The city currently doesn't have enough buses to transport all those people who would normally drive to get off work. Even if it is not enough, as long as the logic of the mayor is satisfied, even if there is only one bus for commuting, the ozone content will be reduced, and a little less is a little bit.  incorrect

C: Buses operating in hot and humid weather are rarely, if ever, able to run at full capacity. The logic of the mayor is that it only needs to be more than half, not full capacity.  incorrect

D: Vehicle emissions in cities do not increase significantly on hot, humid days. This has nothing to do with the mayor's argument. If there is no increase, according to the mayor's algorithm, if the number of buses is more than half, it will be environmentally friendly.  incorrect

E: Not all commuter routes are used by enough people to warrant bus service to them. This option is similar to option B, one more is one, and whether there are enough buses has nothing to do with the mayor's argument.  incorrect

wadhwakaran · Answer

Conclusion: Ozone levels will be lower as long as the buses are more than half full. In simple words if buses are taking more than 20 people, the ozone levels will be lower.

Basis for Conclusion: A bus can carry about 40 people but produces only about 20 times as much exhaust as a car. In simple words, 40 people can commute by producing 20y exhaust i.e. person/exhaust=y/2

Gaps: What if the cars are taking more than 1 person than person/exhaust=y/2 or any number greater; the conclusion breaks

A. Most of the people who would take the special free buses are currently members of carpools.  Correct (this shows that people in a car are greater than 1)

B. The city does not currently have enough buses to transport all of the commuters who normally commute by car.  Even if the proposal is able to reduce half of the cars on the street the pollution will be at lower level. This does not break my conclusion

C. Buses that would be operating on hot, humid days would rarely, if ever, be filled to capacity.  This is what is already given in the premise that the buses if taking more than 20 people will achieve the goal

D. The amount of vehicle exhaust produced in the city is not significantly higher on hot, humid days.  Does not impact my conclusion

E. Not all commuter routes are used by enough people to warrant providing bus service for them.  Some commuter routes are used by enough people meaning thereby that they will use bus and hence the pollution level will be lower. Strengthens the conclusion

VerbalBot · Answer

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Vehicle exhaust produces dangerously high ozone levels in our city in

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