What type of relationship occurs when two variables both increase or decrease together?

How have the competing explanations' experiments on atoms affected the development of the atomic model?

The air that we breath is made mostly of which gaseous molecule

You are driving directly behind a pickup truck, going at the same speed as the truck. a crate falls from the bed of the truck to the road. (a) will your car hit the crate before the crate hits the road if you neither brake nor swerve? (b) during the fall, is the horizontal speed of the crate more than, less than, or the same as that of the truck?