sandy wrote:
For hot desert locations with access to seawater, a new greenhouse design generates freshwater and cool air. Oriented to the prevailing wind, the front wall of perforated cardboard, moistened and cooled by a trickle of seawater pumped in, cools and moistens hot air blowing in. This cool, humidified air accelerates plant growth; little water evaporates from leaves. Though greenhouses normally capture the heat of sunlight, a double-layered roof, the inner layer coated to reflect infrared light outward, allows visible sunlight in but traps solar heat between the two layers. This heated air, drawn down from the roof, then mixes with the greenhouse air as it reaches a second seawater-moistened cardboard wall at the back of the greenhouse. There the air absorbs more moisture, which then condenses on a metal wall cooled by seawater, and thus distilled water for irrigating the plants collects.
For the following question, consider each of the choices separately and select
all that apply.
3. It can be inferred that the process described in the passage makes use of which of
the following?
A The tendency of hot air to rise
B The directional movement of wind
C The temperature differential between the sea and the desert
For the following question, consider each of the choices separately and select
all that apply.
4. It can be inferred that the greenhouse roof is designed to allow for which of the following?
A The avoidance of intense solar heat inside the greenhouse
B The entry of sunlight into the greenhouse to make the plants grow
C The mixture of heated air with greenhouse air to enhance the collection of moisture
Practice Questions
Question: 3,4
Page: 72
Difficulty: hard
This is a very clear and easily "drawable" passage. One can really see the entire thing while reading it, thereby easing choosing the answer choices
Attacking the first question
A-->Well yes it is true that hot air rises, yet is it specified in the passage?TBH not, and this is a classical trick that one would be able to fall into with GRE passages and especially deceptive answer choices. There A is INCORRECT
B--> well in the passage it is specified with the following sentence "Oriented to the prevailing wind, the front wall of perforated cardboard, moistened and cooled by a trickle of seawater pumped in, cools and moistens hot air blowing in." So here we are able to clearly discern that the wind's directional movement is at this cardboard wall of some sort. Basically the wind blows at the wall, since the wall positioned in such a way to catch those wafts. CORRECT
C-->We have this stressed throughout the entire passage that the seawater is cooling the greenhouse. CORRECT
Attacking the second question:
A-->we have this clearly stated in the the following sentence "Though greenhouses normally capture the heat of sunlight, a double-layered roof, the inner layer coated to reflect infrared light outward, allows visible sunlight in but traps solar heat between the two layers" The part that says traps solar heat between the two layers is the thing we were looking for CORRECT
B-->again looking at the aforementioned sentence, we can see "that allows visible sunlight", which we are able to conclude is "of course" beneficial for the plants from the passage is a result of the rooftop CORRECT
C--->Looking at this one we are able to conclude that without the warm air that is derived from the rooftop aids the process of condensation. In the following sentence we are able to determine that after it mixes there is more condensation at the location then it was previously "There the air absorbs more moisture, which then condenses on a metal wall cooled by seawater, and thus distilled water for irrigating the plants collects."
How I would interpret it, were it that we wouldn'T have this effect, there would be condensation, yet less. Thereby this answer choice clearly states that the rooftop is designed to aid the process of amplifying the condensation process. CORRECT
11 Feb 2016, 07:08
29% (02:23) correct
