In Alysha's experiment, she is testing how different materials (tinfoil, plastic wrap, paper, and no cover) affect the melting rate of ice.
- The independent variable is the type of cover material, as this is what Alysha is changing in the experiment.
- The dependent variable is the mass of the ice after 30 minutes, as this is what she is measuring to determine the effect of the independent variable.
Therefore, the correct answer is:
(Choice D) The dependent variable is the mass of the ice, and the independent variable is the type of cover material.