Answer:
Angle of inclination is the independent variable.
Distance covered by the rolling ball is the dependent variable.
Step-by-step explanation:
An independent variable is the one whose variation is not dependent on the value of any other variable while dependent variable changes its value with a change in the independent variable.
In this experiment, angle of inclination (angle between a line and the x-axis) is an independent variable whereas the the distance covered by the rolling ball is a dependent variable which will vary with a change in angle of inclination.