Alysha wants to test the effect of different materials on the melting rate of ice. She finds the initial mass of four pieces of ice. She then covers three pieces with either tinfoil, plastic wrap, or paper. The fourth piece is left uncovered.
After 30 minutes, Alysha calculates the final mass of each piece of ice to determine which melted the fastest.
What are the independent and dependent variables in Alysha's experiment?

a) The dependent variable is the type of cover material, and the independent variable is the mass of the ice.
b) The dependent variable is the mass of the ice, and the independent variable is the time the ice takes to melt.
c) The dependent variable is the mass of the ice, and the independent variable is the type of cover material.
d)
The dependent variable is the time the ice takes to melt, and the independent variable is the type of cover material.