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

[EX Q]: What are the three types of symbiosis?
[EX A]: mutualism, parasitism, commensalism

[EX Q]: What is the term for the movement of molecules from an area of high concentration to an area of low concentration?
[EX A]: diffusion

[EX Q]: What type of motion only occurs when there is one force applied at the beginning of the trajectory after which there is no interference apart from gravity?
[EX A]:
projectile