Given a scientific question and its correct answer, generate supporting facts for the answer. This supporting fact can be an explanation for the answer to the given question.

Question: When the volume of a gas is decreased, what happens to its pressure? Answer: increases
When the volume of a gas is decreased, its pressure is increased.

Question: What else besides temperature has an effect on the phase of a substance? Answer: pressure
Butter is a fat that is a solid at room temperature. What type of fatty acid does butter contain? How do you know?.

Question: Exposure to what causes skin color to darken? Answer: sunlight
Skin color darkens when exposed to the sun.