What is the luminosity of a star? A.
the measure of absolute magnitude
B.
the measure of its distance from the Earth
C.
the measure of radius of a star
D.
the measure of total energy output
E.
the measure of its surface temperature

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