The gravity of Earth is attracting a person towards the center with 500N of gravitational force. The person is exerting a reactionary force on the Earth with how much force? Explain your thinking behind this.

The famous scientist galileo galilei did several experiments with sloping planes, which he rolled metal balls down so that he could study motion. by changing the slope, he could study how the speed at which the ball rolled was affected. what was the independent variable in galileo's experiment? a. the speed of the ball b. the slope of the plane c. whether the ball moved d. what the ball was made of