(____)A. I have two storybooks.
(____)B. It's a maths book.
(____)C. I lost my schoolbag.
(____)D. It's a fat panda.
(____)E. I have three keys in my schoolbag.
“物以类聚,人以群分。”这是一句俗语,重庆人说得更明白:“好人和好人打堆,坏人和坏人打堆。”这里的“打堆”即相处,在一起的意思。这提醒我们( )
已知圆柱的底面半径为3,高为8,求得这个圆柱的侧面积为( )