In this task, you are given a question and answer for that. The answer will fill in the blank or will complete the unfinished question. Your task is to provide an explanation based on the given question or fill-in-the-blank statement, and answer.

[Q]: Question: Ray was traveling in rocket leaving orbit. He keeps the empty fuel containers on board so the ship can fly
Answer: lower
[A]: By using multiple stages, empty fuel containers could drop away. This reduced the mass of the rocket so that it could fly higher.

[Q]: Question: Geremy went to the gym frequently, while Tim did not. Who likely has larger muscles?
Answer: Geremy
[A]: Exercising muscles increases their size, and bigger muscles have greater strength.

[Q]: Question: Theresa lives in a first world country. Eric lives in a third world country. Whose country likely produces less hazardous waste?
Answer: Eric's
[A]:
Countries with more industry produce more hazardous wastes than those with little industry.