A:家庭保障
B:制度保障
C:物质保障
D:法律保障
一个圆柱体和一个圆锥体的底面积和高都相等,已知它们体积之和是48立方分米,圆柱的体积是____.
— I called you yesterday evening, but there was no answer.
— Oh , I’m sorry I _________ dinner at my friend’ s home.