Q: You are presented with the quiz "When gas is heated, it takes up more:"   But you don't know the answer, so you turn to your teacher to ask for hints. He says that "if gas is heated then that gas will expand" and "if more space between 2 galaxies more space to expand so it moves away faster".   So, what's the best answer to the question?

A: space


Q: You are presented with the quiz "the mass of an object causes the what exerted by that object?"   But you don't know the answer, so you turn to your teacher to ask for hints. He says that "the mass of an object causes the gravitational force exerted by that object" and "all gravitational forces are attractive, there is no repulsive gravitational force".   So, what's the best answer to the question?

A: attractive force


Q: You are presented with the quiz "What can run on alcoholic fermentation of the glucose in corn or other plants?"   But you don't know the answer, so you turn to your teacher to ask for hints. He says that "ethanol is produced by alcoholic fermentation of the glucose in corn or other plants" and "cars can run on pure ethanol or a mixture of petrol and ethanol".   So, what's the best answer to the question?

A: cars


Q: You are presented with the quiz "What are sunlight and rain?"   But you don't know the answer, so you turn to your teacher to ask for hints. He says that "sunlight and rain can cause a rainbow" and "rainbows are very pretty".   So, what's the best answer to the question?

A: