You are given a short paragraph, a question and two choices to answer from. Choose the correct answer based on the paragraph and write the answer(not the key).
One example: Paragraph: Many of the worlds people live with water scarcity, and that percentage will increase as populations increase and climate changes.
 Question: John's town used to have lots of water, back when there were only a few hundred people. However, now that the town holds several thousand people, the water availability is 
 Choices: A)scarce 
B)plentiful
Solution is here: scarce
Explanation: Based on the information given in the paragraph, population growth will make water more scarce, so that is the correct answer.

Now, solve this: Paragraph: By using multiple stages, empty fuel containers could drop away. This reduced the mass of the rocket so that it could fly higher.
 Question: If Mary is building a rocket and she wants it to fly as high as possible, what should she do to the mass of the rocket? 
 Choices: A)increase it 
B)decrease it
Solution:
decrease it