Here's a hint that my professor provides:

When and object is completely submerged in a fluid, its apparent weight is equal to its true weight minus the upward acting buoyant force: .

Write this equation for each fluid; once for the case that the object is submerged in ethyl alcohol and once for the case that it is submerged in water. The unknown volume

*V*will appear in the expression for the buoyant force

*FB*. Combine the two equations and solve for

*V*.

Teach me how to solve it please!