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).

[EX Q]: 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: David is getting ready to fly into space on a rocket. As the rocket shoots upwards, part of the mass falls away, allowing the rocket to go
Choices: A)higher
B)lower
[EX A]: higher

[EX Q]: Paragraph: At higher concentrations, particles of reactants are crowded closer together, so they are more likely to collide and react.
Question: DJ has a solution that he adds particles to. The solution is now a _____ concentration.
Choices: A)higher
B)lower
[EX A]: higher

[EX Q]: Paragraph: The closer to the surface an aquifer is, the easier it is to get the water.
Question: If Milo is hunting for water and he finds two water sources, which one will it be easier for him to extract water from?
Choices: A)one close to the surface
B)one far from the surface
[EX A]:
one close to the surface