Net force?? A block w/ height H, area A, and density half that of water floats (in H2O).?

Question

A block w/ height H, area A, and density half that of water floats (in H2O). You depress the block so that an extra length y is submerged past the equilibrium. When you release the block, what is the net force acting on it?

Answer 1

F= Fb1 - W since
V= AH we have
Fb1= g p(H2O)V =
W= mg= g p(material) V

F= g p(H2O)V -g p(material) V
F= g p(H2O)V(1 - 0.5)
F=9.81 x 1000 x AH(0.5)=
F=4905 AH Newtons