题目

用一个高是60cm的圆锥形容器盛满油，倒入和它等底等高的圆柱形容器中，油面的高度是_____cm。 答案：【答案】20【解析】等底等高的圆柱和圆锥，圆柱的体积是圆锥体积的3倍，由此求解。根据分析，油在圆柱容器内的高是圆锥容器内高的，60×＝10（cm），所以油面高度是20cm。 －Oh, it's you, Li Hua! I ________ you． －Sorry．We haven't seen each other for years．I'm wearing glasses now． [　　] A． didn't recognize B． haven't noticed C． didn't know D． haven't found