Reading comp PrepTest 125 · Section 1 · Question 10

Passage

Questions 6-12 Passage A  .        Drilling fluids, including the various mixtures  . known as drilling muds, play essential roles Remaining source text redacted.
Passage walkthrough
Passage Summary

Topic: Science


Passage A

Paragraph 1

  • Paragraph note
    • Purposes of drilling muds
  • Views, minor Meta-Structures, points of intersection, and the author's attitude
    • List of many purposes

Paragraph 2

  • Paragraph note
    • Ingredients of drilling muds
  • Views, minor Meta-Structures, points of intersection, and the author's attitude
    • Bentonite + others
    • Largest ingredient - Barite

Paragraph 3

  • Paragraph note
    • Formulas and problem
  • Views, minor Meta-Structures, points of intersection, and the author's attitude
    • Companies have proprietary formulas
    • Problem - Studying impact since formulas are hidden, have different names for ingredients...

Passage B

Paragraph 1

  • Paragraph note
    • Background and concern
  • Views, minor Meta-Structures, points of intersection, and the author's attitude
    • Background on drilling mud
    • Discharge of drilling mud - Main environmental concern
    • Regulated and monitored

Paragraph 2

  • Paragraph note
    • One type of mud - WBM - Safer
  • Views, minor Meta-Structures, points of intersection, and the author's attitude
    • Water-Based Mud (WBM) - Safer, shallow drills, dumped

Paragraph 3

  • Paragraph note
    • Another type of mud - OBM - Compared to WBM - Regulations
  • Views, minor Meta-Structures, points of intersection, and the author's attitude
    • Oil-Based Mud (OBM) - Deeper wells, more dangerous
    • Compared to WBM - Don’t disperse as readily, more oil, more barite
    • Barite can hurt sea creatures
    • Regulations on dumping

Main Points:

Passage A - Drilling muds have many purposes, are made up of certain chemicals, and have different formulas for different companies, which has presented problems in studying their effects.

Passage B - The release of WBMs is less harmful to the environment than OBMs, which is reflected in the stricter regulations facing the latter.

Key Lines?

Passage A:

  • Lines 2-3 - Introduce the purpose of Paragraph 1
  • Lines 14-15 - Main ingredient
  • Lines 23-26 - A problem is noted

Passage B:

  • Lines 33-35 - A problem
  • Lines 48-54 - Differences

Meta-Structure? Relationship Between Passages?

This is a weird set of passages in that they’re both largely informative - they don’t really have an argument or a point of view. Rather, we get information about drilling muds in both. There’s some overlap - they both talk about the compositions of drilling muds - but also a lot of information that’s unique to one passage - e.g., Passage A’s discussion of the purpose of drilling muds. Since these passages are largely devoid of viewpoints, we should expect the questions to bring up the details, which means that knowing what information is present in each passage is going to be important.

Problem/Solution - Both passages bring up environmental concerns from the dumping of drilling muds. Passage A talks about the “effects of drilling waste discharges” since they have “sometimes toxic” ingredients (Lines 24-26), and Passage B talks about how OBMs have “a greater potential for negative environmental impact” (Lines 52-53). Neither offers a solution other than regulating these products - these passages aren’t about a solution to it but rather just presenting the information about the drilling muds and the problems they post.

Lists (List of Differences)- Both passages include a list. Passage A lists a bunch of purposes of drilling muds in Paragraph 1; Passage B lists differences between OBMs and WBMs in Paragraph 3.

Last Thoughts?

These passages are...boring, for lack of a better word. So it’d be easy to gloss over the information. And there’s also no reason to try to remember all of the key terms, as they’re not things that are familiar to you (bentonite, barite, polymers, etc…). Instead, know what type of information shows up where in each paragraph, and move to the questions as soon as possible so you can spend more time referring back to those details.

Question prompt

Each of the following Remaining source text redacted.
Why the credited answer is right

Credited answer: B

The notes below walk through why it fits the stem and how to eliminate the rest.

Question Type

Science

Strategy Overview

Go straight to the answers, and eliminate those that have information backing them up in either passage, relying heavily on your notes to find the relevant information

Answer Anticipation

This question is...rough, and it’s all about time management. The correct answer here won’t be mentioned in either passage, so to prove the correct answer we’d need to check both passages and see that the answer is missing. Or, alternatively - and what we’re going to do - we can eliminate answers that show up in at least one passage.So let’s head straight to the answers since there’s no guidance as what is going to show up in right or wrong answers and make eliminations on answers that we can quickly identify as being included in at least one passage, then use our notes for the ones that are left to find which show up in a passage and which doesn’t.

Answer choices

  1. A
    Drillers monitor the suitability Remaining source text redacted.
    Why choice A is not credited

    (A) (Lines 43-46) Passage B talks about the disposal of WBMs, where they’re recycled until “their properties are no longer suitable.” The only way to know that is to monitor it, so this answer is supported by the second passage.

  2. B
    The government requires drilling Remaining source text redacted.
    Why choice B matches the stem

    (B) (Lines 28-30) Passage A says that a difficulty in studying drilling muds is that “many [ingredients are] kept secret by companies or individual formulators,” so this answer is contradicted by that passage. Passage B discusses dumping regulations, but not disclosure of ingredient regulations. As such, this answer isn’t supported by either passage, making it correct.

  3. C
    In certain quantities, barite Remaining source text redacted.
    Why choice C is not credited

    (C) (Lines 16-19) We just saw this come up in Question #9 with the correct answer. Passage A talks about using barite in food and medical procedures, so it must be safe for humans at least in certain quantities.

  4. D
    Oil reserves can be Remaining source text redacted.
    Why choice D is not credited

    (D) (Lines 5-6) Passage A provides a list of reasons why drilling mud is used, including “cool[ing] the drill bit as it cuts into the rock,” supporting this answer.

  5. E
    Drilling deep oil wells Remaining source text redacted.
    Why choice E is not credited

    (E) (Lines 38-40; Lines 47-48) Passage B talks about using WBMs for shallow wells and OBMs for deeper wells, supporting this answer.

What this tests

Question analytics

Based on historical answer selection rates for this question.

Answer choice distribution

  1. A 4%
  2. B Credited 78%
  3. C 6%
  4. D 10%
  5. E 2%

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