题目
求下面组合体的体积和表面积.(单位:米)
(1)
(2)
答案: 解:[4×8+4×(1+1)+8×(1+1)]×2+(2×1+2×8)×2 =[32+8+16]×2+(2+16)×2 =56×2+18×2 =112+36 =148(平方米); 4×8×(1+1)+2×1×8 =32×2+16 =64+16 =80(立方米); 答:它的表面积是148平方米,体积是80立方米。
(0.6×0.4+1×0.6)×2+(1×0.2+1×1.6+0.2×1.6)×2 =(0.24+0.6)×2+(0.2+1.6+0.32)×2 =0.84×2+2.12×2 =1.64+4.24 =5.88(平方米); 1×0.6×0.4+1×0.2×1.6 =0.24+0.32 =0.56(立方米); 答:它的表面积是5.88平方米,体积是0.56立方米。