Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Input: Consider Input: The pressure of a sample of gas is measured with an open-end manometer.

Output: The pressure of a sample of gas is measured with an open-end what?

Input: Consider Input: The sun and the moon appear to be about the same size in the sky because the moon is smaller in diameter and is closer to earth than the sun.

Output: Which statement best explains why the Sun and the Moon appear to be about the same size in the sky?

Input: Consider Input: Energy do ecosystems absorb on the earth.
Output: What do ecosystems absorb on the earth?