Cloud seeding can aid precipitation in three ways. Static mode seed

Official Explanation From Veritas Prep

1) Which of the following most accurately mimics the process of cloud seeding, as it is described in the passage above?
A) Making snow at a ski area by pumping water through pipes into snow guns, so that snow pack is increased along trails.
B) Fertilizing fruit trees in an orchard, so that they produce more fruit and do so more reliably.
C) Raising interest rates in a country, so that growth and inflation slow down to a sustainable rate.
D) Creating underwater aquaculture farms, so that mussels and oysters can flourish in places they would not naturally.
E) Constructing desalination plants, so that unusable salt water can be transformed into usable fresh water.

Solution - For this type of “mimic the reasoning” question, you need to summarize the process of cloud seeding from your initial reading, and then look for the answer that best matches that summary. In the passage, you should note that cloud seeding is a way to stimulate a natural process: by adding an artificial element into naturally forming clouds, precipitation can be enhanced. So you should be looking for the answer that best describes the artificial enhancement of a natural process.

While (A) might seem correct (since it relates to creating precipitation), snowmaking is a completely artificial process. The correct answer must be enhancing an already natural process and (B) matches this perfectly. Fertilization, like cloud seeding, involves enhancing a natural process (in clouds, the production of rain, and in fruit trees, the production of fruit) so this is correct. While (C) does relate to artificial influence on a “natural” process – the economy – the correct answer must be enhancing the process, not limiting it. (D) might be tempting but says “so that they flourish in places they would NOT naturally.” Therefore this is not enhancing an already natural process. If cloud seeding involved creating the clouds themselves, then indeed this would be correct. For (E), since this answer relates to producing more water (the subject matter of cloud seeding), some might find it correct. However, it has nothing to do with enhancing an already natural process so it can be confidently eliminated. Remember that in “mimic the reasoning” questions, it is not the topic that needs to be mimicked, but rather the overall logic. Only (B) matches the process of cloud seeding and is thus correct.

2) Which of the following would the author most likely regard as an accurate description of the prospects for successful cloud seeding?
A) Moderately encouraging
B) Vastly underrated
C) Inherently limited
D) Virtually non-existent
E) Impossible to gauge

Solution - This passage is primarily explanatory/descriptive but there is some subjectivity at the end of the passage: the final sentence states that “The difficulties of making this a reality are, however, substantial, and in some cases, insurmountable.” Clearly not everyone would agree with that and the author has inserted some mild opinion to end the passage (although that is not the primary intent). You should always note any subjectivity in a reading comp passage, as questions are usually made to assess it.

Given that final sentence, you know the author has a mildly negative view about the prospects for effective cloud seeding, so you should find the answer that best matches that tone. For (A), nothing in the final paragraphs suggests the author is particularly encouraged about the prospects of effective seeding. For (B), the author is not suggesting that cloud seeding is somehow better than most people believe. For (D) and (E), both of these are far too strong and therefore easy to eliminate: the author seems to believe that successful seeding is possible but unlikely, and the author believes that the success of seeding is difficult to gauge, but not impossible.

Only (C) gets the author’s mild tone correct: the use of the word “insurmountable” in the passage implies inherent or built-in limitations and “limited” matches the mildly negative tone noted earlier. The correct answer is (C).

3) In cloud seeding, which one of the following is mentioned as a factor in determining the form of precipitation that hits the ground?
A) The temperature in the upper portions of the clouds that are seeded
B) Whether silver iodide or dry ice crystals are used to seed the clouds
C) The number of crystals that are added to the clouds
D) The temperature at the surface below the cloud seeding
E) The type of cloud that is seeded

Solution - For this type of “specific” question, you need to go find where the unique keywords given in the question stem (in this case “form of precipitation that hits the ground are discussed.” Since the details of cloud seeding are mentioned mainly in the 1st paragraph, you should focus your attention there. The correct answer will be stated explicitly, albeit with different (and sometimes tricky) wording, or it might just be well hidden.

In the first paragraph you find: “The ice embryos that are formed can, if conditions are favorable, grow into snowflakes that fall to the ground as either snow or rain, depending on surface temperatures.“ From this you can conclude definitively that (D) is correct: the surface temperature definitely affects whether the precipitation is snow or rain. If you find that quickly and match it to (D), this problem is relatively straightforward. However, some of the other answers seem to be correct also, and only a close reading can eliminate them.

For (A), it would seem that the temperature in the upper portion of the clouds would be important, but it does not matter for what hits the ground. The passage only states that the temperature in the upper portion of the clouds allows cold cloud seeding in warmer weather, but says nothing about how this will affect the form of precipitation at ground level. For (B), there is no mention of any important difference at all between those two types of seedings, yet alone in relation to the form of precipitation. (C) is tricky as you learn in the passage that “ [when] a larger number of crystals are added…the resulting freezing releases heat, thereby increasing the size and longevity of the cloud.” So the number of crystals affects the cloud formation, but that still tells you nothing about the form of precipitation that will hit the ground. Lastly for (E), nothing is given in the passage that relates the type of cloud to the type of precipitation that hits the ground, so this too can be eliminated. Only (D) is explicitly stated in the passage and is thus correct.

4) The author of the passage is primarily concerned with
A) providing an overview of the mechanics and difficulties of cloud seeding
B) arguing for a more realistic approach to cloud seeding
C) giving a brief history of cloud seeding
D) comparing the methods used to seed clouds
E) acknowledging that cloud seeding is unlikely to be very useful in the future

Solution - For any primary purpose question, the correct answer needs to match the type of passage (opinionated or explanatory/descriptive) and the scope of the passage. You must also make sure that the correct answer is exactly “on-topic” to the content of the passage.

In this example, the passage is almost exclusively explanatory/descriptive, although there is some mild subjectivity in the last paragraph. The first two paragraphs provide the overview of the mechanics of cloud seeding (including a few challenges), while the rest of the passage focuses more on the challenges.

Given this, you can first eliminate answer choice (B), as the primary purpose is to convey information, not “argue” anything. Also, the word “acknowledging” in (E) suggests it should be a more opinionated passage overall, and this answer is far too narrow in scope - the difficulties are just one part of the passage and the passage exists more to describe those difficulties than to acknowledge them.

Answer choice (C) is decidedly off topic, as no history is given within the passage. For (D), the first two paragraphs mainly describe the three different types of seeding and the comparisons made between them are minimal. Even with some comparisons made in the passage, this answer is far too narrow in scope and does not capture the overall purpose.

Only (A) gets everything correct – “providing” matches the type of passage perfectly and “the mechanics and difficulties of cloud seeding” is exactly on scope and on topic. The correct answer is (A).

5) According to the passage, cloud seeding can increase the size of a cloud by
A) creating water droplets through the introduction of condensation nuclei.
B) causing supercooling to take place in the upper portion of cumulus clouds.
C) carefully targeting continental clouds at the right stage in their development.
D) using a larger number of ice crystals than is used in static mode seeding.
E) using salt crystals to release heat that expands cloud particles.

Solution - For this type of “specific” question, you need to go find where the unique keywords given in the question stem (in this case “cloud seeding can increase the size of a cloud”) are discussed. Since the details of cloud seeding are mentioned mainly in the 1st paragraph, you should focus your attention there. The correct answer will be stated explicitly, albeit with different (and sometimes tricky) wording, or it might be well hidden, as in this problem.

With so much specificity in the question stem, you should first find exactly where an increase in the size of clouds is discussed. In the 1st paragraph, after a discussion of static mode seeding, the author states that: “In dynamic seeding, a larger number of crystals are added. The resulting freezing can release heat, thereby increasing the size and longevity of the cloud.”

Given this section, you should see that (D) is correct: “a larger number of crystals [than in static seeding]” results in an increase in cloud size. For (A), “condensation nuclei” was only discussed regarding hygroscopic seeding (the third method) and there is no discussion of an increase in cloud size there. Similarly for (B), supercooling is only discussed in relation to cold cloud seeding (the first method) and no relation to an increase in cloud size is given. For (C), there is no link given in the passage between the timing of seeding or the type of cloud and an increase in the size of clouds. For (E), salt crystals were only discussed in relation to hygroscopic seeding (the third method) and as with (A), there is no discussion in the passage of whether this increases cloud size. The correct answer is (D).