The Mediterranean Sea sedimentary record reveals intermittent black se

Question

The Mediterranean Sea sedimentary record reveals intermittent black sediment layers that seem to represent environmental changes over time. These layers, darkened by organic matter, rare in most ocean sediments, indicate the presence of a strong, physical control. Some geologists credit "reverse circulation," wherein waters flowing inward from the Atlantic Ocean are flushed back out in a reverse flow by the constant influx of fresh water from the several rivers that feed the sea. As surface waters evaporate, the heavily salted remnant, containing less dissolved oxygen, sinks. During intensely wet periods, soil nutrients fertilize the surface, phytoplankton production increases, and evaporation dissipates, creating an organically rich environment.

However, sedimentary records show bottom-dwellers coexisting with the dark layers were oxygenstressed, so, reverse circulation could not have existed. Milankovitch Cycles, associated with earth-sun positional relationships, which change the dates of the equinoxes/solstices in 20,000 year cycles, are more likely. Climatic effects include intense rainy seasons depending on the earth's tilt, orbital eccentricity, and distance from the sun. Additionally, the 20,000 year cycles match the spacing of dark layers in the Mediterranean record.    1 
 1. Which of the following can be inferred from the passage?

A. Milankovitch cycles are affected by the size of the earth's orbit
B. dark layers of sediment could indicate climate changes in history
C. dark sedimentary layers are caused by the presence of inorganic matter
D. Milankovitch cycles cause rainy seasons
E. phytoplankton are present in the ocean only during wet weather cycles

2 
 2. The author is primarily concerned with

A. analyzing the source of a geological controversy
B. describing a geological phenomenon
C. criticizing a scientific theory
D. proposing a new theory to explain existing scientific evidence
E. pointing out the flaws in a geological study

3 
 3. The author of the passage would most likely agree with which of the following about Milankovitch Cycles.

I. The eccentricity of the earth's orbit is the least important of the causes of the seasons.
II. The sun is gradually changing position relative to the earth over 20,000 year periods of time.
III. The dates of the equinoxes and solstices change over time.

A. I only
B. II only
C. III only
D. I and III
E. II and III

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 Passage # 04  |  Date: 02 March 2023 
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$!vakumar.m · Answer

1. Which of the following can be inferred from the passage?

A. Milankovitch cycles are affected by the size of the earth's orbit  
Infact it is the intense rainy seasons (caused by M cycles) which depend on the earth's tilt, orbital eccentricity, and distance from the sun.

B. dark layers of sediment could indicate climate changes in history 
Enough evidence is given in the passage which suggests that the dark layers seem to represent environmental changes over time. These layers indicate the presence of a strong, physical control - earlier credited to "reverse circulation" and later to "M cycles" - both resulting in climatic changes over period of time.
 
  C. dark sedimentary layers are caused by the presence of inorganic matter  
rather the layers are darkened by organic matter which are rare in most ocean sediments.

D. Milankovitch cycles cause rainy seasons  
the passage suggests that climatic effects (due to M cycles) include intense rainy seasons which depend on the earth's tilt, orbital eccentricity, and distance from the sun. Other factors are also involved to cause rainy seasons.

E. phytoplankton are present in the ocean  only  during wet weather cycles  
Para 1 - suggests that phytoplankton production increases during intense wet periods and not that phytoplankton are present in the ocean only during wet periods.

3. The author of the passage would most likely agree with which of the following about Milankovitch Cycles. 
the info given in the passage on M cycles are
Milankovitch Cycles, associated with earth-sun positional relationships, which change the dates of the equinoxes/solstices in 20,000 year cycles, are more likely. Climatic effects include intense rainy seasons depending on the earth's tilt, orbital eccentricity, and distance from the sun. Additionally, the 20,000 year cycles match the spacing of dark layers in the Mediterranean record.
  I. The eccentricity of the earth's orbit is the least important of the causes of the seasons.  
no evaluation of the various factors which affect the climate changes have been carried out. 
  II. The sun is gradually changing position relative to the earth over 20,000 year periods of time.  
the dates of equinoxes/solstices changes in 20,000 year cycles and not the relative position of the Sun wrt earth.
  III. The dates of the equinoxes and solstices change over time.  
True as explained above.
Answer C

1. B ; 3 C

Elite097 · Answer

1. Which of the following can be inferred from the passage?

A. Milankovitch cycles are affected by the size of the earth's orbit--- "Milankovitch Cycles, associated with earth-sun positional relationships in 20000 year cycles" indicates that size is of importance as that will affect positional relationship 
B. dark layers of sediment could indicate climate changes in history-  cannot infer this 
C. dark sedimentary layers are caused by the presence of inorganic matter---- exactly the opposite statement was said in the passage; passage says 'These layers, darkened by organic matter 
D. Milankovitch cycles cause rainy seasons-  "Climatic effects include intense rainy seasons" is different from saying these cycles caused the seasons themselves. this part is just about intensity. 
E. phytoplankton are present in the ocean only during wet weather cycles---  we cannot conclude what is 'only' possible. We just know they increased during those cycles

Ans A

2. The author is primarily concerned with

A. analyzing the source of a geological controversy--  source is not the primary concern here 
B. describing a geological phenomenon--- a phenomenon is discussed but that is not the primary concern and passage goes beyond just descriing a phenomenon 
C. criticizing a scientific theory--  no criticism is shown 
D. proposing a new theory to explain existing scientific evidence---  evidence is the dark matter and a new theory has been used to explain this - milankovich cycles, instead of 'reverse circulation' 
E. pointing out the flaws in a geological study---  flaws have not been actively discussed in the passage

Ans D

3. The author of the passage would most likely agree with which of the following about Milankovitch Cycles.

I. The eccentricity of the earth's orbit is the least important of the causes of the seasons.--  we have no info for making this comparison 
II. The sun is gradually changing position relative to the earth over 20,000 year periods of time-- since the cycles are dependent on earth sun relationships and they change over 20000 year cycles, thus thus can be inferred 
III. The dates of the equinoxes and solstices change over time.--- "which change the dates of the equinoxes/solstices in 20,000 year cycles" from this we cant infer whether dates are changed over time or in one go

Ans B

Ps1810 · Answer

In my opinion the answers are:
1-b
2-d
3-e

Oppenheimer1945 · Answer

1. Which of the following can be inferred from the passage?

A. Milankovitch cycles are affected by the size of the earth's orbit 
 B. dark layers of sediment could indicate climate changes in history (Additionally, the 20,000 year cycles match the spacing of dark layers in the Mediterranean record.) 
C. dark sedimentary layers are caused by the presence of inorganic matter
D. Milankovitch cycles cause rainy seasons
E. phytoplankton are present in the ocean only during wet weather cycles
B)

Milankovitch Cycles, associated with earth-sun positional relationships, which change the dates of the equinoxes/solstices in 20,000 year cycles, are more likely. Climatic effects include intense rainy seasons depending on the earth's tilt, orbital "eccentricity", and distance from the sun.

2. The author is primarily concerned with

A. analyzing the source of a geological controversy(author is doing extensive analysis for a phenomenon: As surface waters evaporate, the heavily salted remnant, containing less dissolved oxygen, sinks. During intensely wet periods, soil nutrients fertilize the surface, phytoplank)  
B. describing a geological phenomenon 
C. criticizing a scientific theory
D. proposing a new theory to explain existing scientific evidence
E. pointing out the flaws in a geological study

A)

3. The author of the passage would most likely agree with which of the following about Milankovitch Cycles.

I. The eccentricity of the earth's orbit is the least important of the causes of the seasons. (nowhere in the passage it is mentioned "least important cause"
 II. The sun is gradually changing position relative to the earth over 20,000 year periods of time. (earth-sun positional relationships, which change the dates of the equinoxes/solstices in 20,000 year cycles, are more likely. ) 
 III. The dates of the equinoxes and solstices change over time.earth-sun positional relationships, which change the dates of the equinoxes/solstices in 20,000 year cycles, are more likely. 
 
A. I only
B. II only
C. III only
D. I and III
 E. II and III

E)

Catman · Answer

1. Which of the following can be inferred from the passage?

A. Milankovitch cycles are affected by the size of the earth's orbit ~   Refer to the line "Climatic effects include intense rainy seasons depending on the earth's tilt, orbital eccentricity, and distance from the sun" Climate effects are depending on earth's orbit and not Miankovitch cycle. .

B. dark layers of sediment could indicate climate changes in history ~   Refer to the line "The Mediterranean Sea sedimentary record reveals intermittent black sediment layers that seem to represent environmental changes over time." Other evidences also mention in the passage are related to the climate changes.
 
C. dark sedimentary layers are caused by the presence of inorganic matter ~  Incorrect, as mentioned the black sediment layers are darkened by the organic matter.

D. Milankovitch cycles cause rainy seasons  Climate effect includes intense rainy seasons, but rainy season causes cannot be linked to Milankovitch cycles

E. phytoplankton are present in the ocean only during wet weather cycles ~  Incorrect " During wet weather cycles phytoplankton production increases, but this does not mean that they are present only during the wet winter cycles.

2. The author is primarily concerned with

A. analyzing the source of a geological controversy  Incorrect, Author is not analyzing the source of controversy. Author is proposing a new theory over an exisisting one.

B. describing a geological phenomenon  Incorrect geological phenomenon are mentioned, but author proposes that Milankovitch Cycles,cause climatic effects and not "Reverse Circulation"
 
C. criticizing a scientific theory  Author is not criticizing Reverse Circulation theory, he proposes a new theory of Milankovitch Cycles

D. proposing a new theory to explain existing scientific evidence  author proposes that Milankovitch Cycles,cause climatic effects over an old theory of reverse circulation.

E. pointing out the flaws in a geological study  Although authors points flaw in the reverse circulation theory but he proposes that Milankovitch Cycles,cause climatic effects.

3. The author of the passage would most likely agree with which of the following about Milankovitch Cycles.

I. The eccentricity of the earth's orbit is the least important of the causes of the seasons.

II. The sun is gradually changing position relative to the earth over 20,000 year periods of time.

III. The dates of the equinoxes and solstices change over time.

I. Refer to the line "Climatic effects include intense rainy seasons depending on the earth's tilt, orbital eccentricity, and distance from the sun". So statement 1 is incorrect as earth tilt, orbital eccentricity are mentioned reason for climatic effects.

II. Refer to the line "Milankovitch Cycles, associated with earth-sun positional relationships, which change the dates of the equinoxes/solstices in 20,000 year cycles, are more likely." It measn that earth-sun positions are changing. Earth position can change, sun position can change, both positions of earth and sun can change. So,Incorrect.

III. Refer to the line "Milankovitch Cycles, associated with earth-sun positional relationships, which change the dates of the equinoxes/solstices in 20,000 year cycles, are more likely. Clearly mentioned that the date of date of equinoxes and solstices are changing over time.
 
A. I only

B. II only

C. III only

D. I and III

E. II and III

zyt · Answer

1. Which of the following can be inferred from the passage?

A. Milankovitch cycles are affected by the size of the earth's orbit  CORRECT.It I mentioned that milankovitvh cycles are affected by distance between sun and earth 
B . dark layers of sediment could indicate climate changes in history 
iINCORRECT dark layers indicated milankovitch cycle according to passage
 
 C. dark sedimentary layers are caused by the presence of inorganic matt 
INCORRECT caused by organic matter.

D. Milankovitch cycles cause rainy seasons   
INCORRECT 
E. phytoplankton are present in the ocean only during wet weather cycles   
INCORRECT Phyto plankton more in wet not only present in wet cycles

2. The author is primarily concerned with

A. analyzing the source of a geological controversy
B. describing a geological phenomenon
C. criticizing a scientific theory 
D. proposing a new theory to explain existing scientific evidence
CORRECT the author proposes milank* theory to explain the black sediments in Mediterranean sea
E.  pointing out the flaws in a geological study

3. The author of the passage would most likely agree with which of the following about Milankovitch Cycles.

I.  The eccentricity of the earth's orbit is the least important of the causes of the seasons.    INCORRECT not stated
II.  The sun is gradually changing position relative to the earth over 20,000 year periods of time.  CORRECT mentioned in 3rd para
III.  The dates of the equinoxes and solstices change over time.  CORRECT mentioned in 3rd para
A . I only
B. II only
C. III only
D. I and III 
 E. II and III

Sajjad1994 · Answer

Hello Everyone

OAs are revealed now

BDC

Competition mode is off now and anyone can see others' replies. Seeing the result, this passage seems hard.

sivakumarm786  (6/10)

Elite097  and Catman (3.5/10)

samagra21  (2.5/10)

zyt  (2/10)

Good luck guys for the Day 3 passages.

Sajjad1994 · Answer

Explanation

1. Which of the following can be inferred from the passage?

Explanation

The passage discusses the possible causes of dark sediment layers found in the Mediterranean Sea, which indicate environmental changes over time. The passage discusses two theories: reverse circulation and Milankovitch Cycles. The first theory suggests that reverse circulation is responsible for the dark layers, while the second theory suggests that Milankovitch Cycles, which affect earth-sun positional relationships, could be the cause. The passage states that sedimentary records show that bottom-dwellers coexisting with the dark layers were oxygen-stressed, which suggests that reverse circulation could not have existed. Therefore, the second theory, Milankovitch Cycles, is more likely to be the cause of the dark sediment layers. Therefore, the correct answer is B: dark layers of sediment could indicate climate changes in history.

Answer: B

Sajjad1994 · Answer

Explanation

2. The author is primarily concerned with

Explanation

The author is proposing a new theory, Milankovitch Cycles, to explain the environmental changes represented by the black sediment layers in the Mediterranean Sea sedimentary record. Therefore, the correct answer is  (D)  proposing a new theory to explain existing scientific evidence.

Answer: D

Sajjad1994 · Answer

Explanation

3. The author of the passage would most likely agree with which of the following about Milankovitch Cycles.

Explanation

The passage clearly states that Milankovitch cycles are  "associated with earth-sun positional relationships, which change the dates of the equinoxes/solstices in 20,000 year cycles."  Therefore, the author would most likely agree with statement III that "the dates of the equinoxes and solstices change over time." The passage does not mention the importance of the eccentricity of the earth's orbit, so statement I cannot be inferred. Statement II is partially correct but does not capture the full picture of Milankovitch cycles.

Answer: C

Elite097 · Answer

Sajjad1994  wy cant st 2 be inferred? what else can it be?

Sajjad1994 · Answer

"The sun is gradually changing position"

This cannot be inferred from the passage. The passage only tells us about earth-sun positional relationships cycle but it did not tells us that specifically sun is gradually changing position.

Elite097 · Answer

How is b an inference when its directly stated in the passage?
Also how does the explanation given lead to B? What do the theories have to do with this?  Sajjad1994

Elite097 · Answer

if sun earth position cycles change every 20000 years means sun is changing right? What else could it mean?  Sajjad1994

Sajjad1994 · Answer

"earth-sun positional relationships"

Sun can change position
Earth can change position
Both can change position
Anything could happen

A could be true answer hence cannot be inferred.

Anandanwar · Answer

Hello,
For Q2:
I rejected D due to partial scope. Can partial scope choices be correct for primary concern questions?
Would that be the same for main point questions?

Regards,
Ankit

glagad · Answer

Hi  Sajjad1994

The passage does mention that earths' orbit causes the Climatic Effects. From the way the passage is structured, I inferred that climatic changes are the result of Milankovitch Cycles, and hence the answer can be A (by the transitive property).

Additionally, I rejected answer B because it talks about "dark layers of sediment" - which is a very broad terminology used. While the passage talks about dark layers, we can't mention that as a generic fact.

Kindly let me know where I faltered.

reed990 · Answer

We can consider the emphasis of this sentence, the sun is gradually changing position "relative to the earth". The position of the sun can change; the position of the earth can change; or scientifically, both are changing. Regardless, according to the passage that "distance from the sun", the relative position of sun to the earth is changing over the 20,000 year period, or it also equals to the statement that relative position of the earth to the sun is changing over this period. Thus, II should also be inferred.

VerbalBot · Answer

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The Mediterranean Sea sedimentary record reveals intermittent black se

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The Mediterranean Sea sedimentary record reveals intermittent black se

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