How Does Temperature Affect the Buoyancy of Lead in Mercury?

[bee]

Homework Statement

Homework Equations

a flat, uniform cylinder of lead float in mercury in 0 degree celsius. Will the lead float higher or lower when the temperature is raised? Explain.

The Attempt at a Solution

 

[kuruman]

What do you know about floating objects? What must be true for an object to float in a fluid? What happens to mercury when its temperature rises?