在一个直径是20厘米的圆柱形容器里，放入一个底面半径3厘米的圆锥形铁块，全部浸没在水中，这是水面上升0.5厘米．圆锥形铁块的高是多少厘米？

I didn't see you these days. Where did you           ? [ ]

A. hang out

B. hung out

C. hanged out

D. hung after