3.14×（12.56÷3.14÷2）²×5=3.14×4×5=12.56×5=62.8（立方厘米）π r² h
底面半径r=12.56 / 2X3.14=2CMS底=3.14x(2)^2=12.56V=S底xh =12.56x5=62.8cm^3
底面周长=12.56,底面半径=12.56/3.14*2=2圆柱的体积=3.14*2*2*3=37.68(立方厘米)
