题干
_____ the front door _____, he had to enter the room through the back door.
A：Seen; painted
B：Seeing; painted
C：Being seen; being painted
D：Seeing; being painted
答案(点此获取答案解析）
D
为自然对数的底数，a为正常数），若经过5分钟时容器A和容器B中的水量相等，经过n分钟容器A中的水只有
，则n的值为 （ ）