Is it possible for a piece of cork to have more mass than a piece of rock?

Yes

Explanation:

It is entirely possible for a piece of cork to have more mass than a piece of rock. This would largely depend on the volume of the two objects. The density of a substance remains the same irrespective of the size of the substance.

                   Density = mass/volume

At constant density, it means that the mass of an object depends only on the volume of the object.

Hence, a piece of cork can weigh more than a piece of rock if the volume or size of the cork is bigger enough than that of the rock.

listen, you cant how young you were.

"you didn't chose the stud life. the stud life chose you."