Reading comp PrepTest 125 · Section 1 · Question 7

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

Which one of the Remaining source text redacted.
Why the credited answer is right

Credited answer: E

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

Question Type

Science

Strategy Overview

Review what each passage said about barite, then find an answer that matches it

Answer Anticipation

We need to find barite in both passages, then identify a shared detail, so we should be heading straight back to the passage.Passage A talks about the composition of drilling muds in Paragraph 2, so we should look there. The discussion of barite starts in Line 15, where we learn:It’s by far the largest ingredient in drilling mud (weight)It’s a very heavy mineral with density 4.3 to 4.6It’s an inert filler in foods and used in medical procedures Now, on to Passage B. Instead of thinking through each thing that the passage says about barite, however, we’re now looking for one of the things we already know about it. Barite should be in Paragraphs 2 or 3, since they discuss the composition of WBMs and OBMs. There’s no mention of barite in Paragraph 2 (just bentonite), so we need to move to Paragraph 3. There, barite shows up in Line 50. Looking through, it starts by saying it’s a powdered heavy mineral, which Passage A also said - so there’s a potential answer. Barite can also impact some organisms such as sea scallops, but that’s not mentioned in Passage A.So the only overlap is that both passages say barite is a heavy mineral - let’s find an answer stating that.

Answer choices

  1. A
    It does not disperse Remaining source text redacted.
    Why choice A is not credited

    (A) (Lines 50-54) Passage A doesn’t discuss this, so it’s wrong. Passage B also says that barite is an ingredient in OBMs, and OBMs don’t disperse readily in seawater, but that doesn’t mean the barite doesn’t disperse readily. Maybe it’s the oil that doesn’t disperse readily, while some ingredients such as barite do. This answer doesn’t show up in either passage, so it’s incorrect.

  2. B
    It is not found Remaining source text redacted.
    Why choice B is not credited

    (B) (Lines 12-15; Lines 38-40; Line 50) Passage A says that drilling muds are made up of bentonite and they include a lot of barite, contradicting this answer. Passage B says that WBMs are made of bentonite, and OBMs include “greater concentrations of barite,” implying WBMs have some - again, contradicting this answer.

  3. C
    Its use in drilling Remaining source text redacted.
    Why choice C is not credited

    (C) Neither passage suggests that the composition of drilling muds is regulated - just where they can be dumped (in Passage B).

  4. D
    It is the most Remaining source text redacted.
    Why choice D is not credited

    (D) (Lines 14-15) Passage A says that it’s the largest ingredient by weight, which isn’t necessarily the same as saying it’s the most common - it really depends on how you define that word. But even if you were hung up on that, Passage B never uses superlative language, so this answer can be eliminated based on that passage.

  5. E
    It is a heavy Remaining source text redacted.
    Why choice E matches the stem

    (E) (Line 15; Lines 50-51) Both passages identify barite as a heavy mineral, making this the correct answer.

What this tests

Question analytics

Based on historical answer selection rates for this question.

Answer choice distribution

  1. A 2%
  2. B 1%
  3. C 1%
  4. D 4%
  5. E Credited 91%

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