You are investigating whether the thickness of a sponge is affected by the amount of mass placed on top of it. What is the dependent variable in this investigation?

The thickness of sponge is the dependent variable in this investigation

Explanation:

This is because in the investigation, the amount of mass is the property to be varied while the thickness of the sponge is the property to be checked.

The thickness of the sponge is dependent on the amount of mass placed on it, so the thickness of the sponge depends on the mass.

Thus, the thickness of the sponge is the dependent variable in this instance while the amount of mass is the independent variable in this investigation.