一个立方体的体积是125cm3,它的棱长是[ ]
A.4cm
B.5cm
C.6cm
D.7cm
答案:B
It's wellknown that the world economic situation will get worse________. [ ]
A. not if dealt carefully with
B. if not carefully dealt with
C. if dealt not carefully with
D. not if carefully dealt with
社会保障制度产生和发展分几个阶段?各阶段的主要标志是什么?