Hydraulics Problem Solved #5: Analyze and Solve with me

A wooden buoy of specific gravity 0.75 floats in a liquid having a specific gravity of 0.85
a. Evaluate the percentage of the volume of the buoy above the liquid surface to the total volume of the buoy
b. if the volume above the liquid surface is 0.045 cubic meters, estimate the weight of the buoy, in kN
c. What vertical force in kN, applied to the buoy to fully submerge it?
*CORRECTION* (mybad)
c. 3190.31 N convert to kN ~ 3.190kN
then, Fv= Fb - Wb
Fv = 3.190 kN - 2.815 kN
Fv = 0.375 kN [FINAL ANSWER]