1 排开水的体积=m/p=0.89/8900=0.0001m^3因为浮力=pgv=1000*9.8*0.0001=0.98N2 270克的铅球体积=m/p=0.27/2700=0.0001m^3所受到浮力=pgv=1000*10*0.0001=1N