(1)F浮=ρ水gV排=1000kg/(m^3)x10n/Kgx3/4x0.2m^3=1500N
(2)G=F浮=1500N
m=G/g=1500N/(10N/Kg)=150Kg
ρ=m/v=150Kg/(0.2m3)=750Kg/m3