Please help with these, I’ll give 33 points and mark brainliest please I need this to get my grade up

In this case, the statement that people who exercise for an hour may have lower cholesterol levels is .

Study this image which statement best describes the rock shown check all that apply

Rarefaction is used for which of the following? a. creating a representative sample b. studying how disease impacts populations c. rediscovering species thought to be instinct d. determining which sea creatures live in an area