안녕하세요!

3번 e문제 학생 답 완전 좋아요. 그대로 적어도 full points!

4번 b의 경우는 조금 애매하긴 해요.

leaves are normally found on the O horizon, above the A horizon.

by the time these leaves are pushed down to A, they are usually decomposed and referred to as humus.

an easier answer related to plants would be the roots, because they often penetrate down to the lower regions of soil.

4c는 좋아요! 그대로 써도 괜찮아요.

fertilizer runoff refers to the movement of fertilizer beyond the intended area it is applied to

and this runoff can later percolate down to the groundwater source.

4d okay, it's acceptable.

because we are talking about the pH composition of soil in which the plant lives,

oftentimes, this change in pH will result in slow or no growth of the plant itself.

so rather than talking about pH inside of the plant, it's easier to talk about the stunted growth or the failure to thrive.

하지만 학생 답변도 과학적으로 맞는 얘기여서 괜찮아요.

4e랑 추가답변은 같이 볼께요.

increased temperature does not directly lead to increased precipitation.

increased temperature directly leads to increased evaporation, leading to more moisture in the air (think rainforest)

this increased moisture in the air can then lead to higher chance of precipitating 

due to a drop in temperature as air rises.

Notice how there are additional steps between increased temperature and increased rainfall. (increased moisture and temperature drop)

4e 문제는 우리에게 increased temperature가 아닌 climate change에 대해서 물어봤기 때문에

extreme weather phenomenon의 일환으로 많은 강수량과 홍수를 생각할 수 있어요.

you don't even need to mention temperature for this,

because claiming extreme weather can occur due to climate change is well established.

so you can say climate change causes drought, or climate change causes floods. 

both are acceptable consequences of climate change, even if they are opposite ends of the spectrum!