Given a scientific question, generate a correct answer to it.

Input: Consider Input: The purpose of scientific investigations generally is to test a what?

Output: hypothesis

Input: Consider Input: The hemolymph and body cells exchange chemicals within what body part?

Output: the sinuses

Input: Consider Input: Many ionic compounds occur as hydrates, compounds that contain specific ratios of loosely bound water molecules, called waters of hydration. waters of hydration can often be removed simply by doing this?
Output: heating