大于0.45而小于0.50的小数有无数个．______．（判断对错）
大于0.45而小于0.50的小数有三位小数、四位小数…，所以有无数个．
故答案为：正确．
The policeman asked the driver _______.
A．when the accident happened
B．when did the accident happen
C．the accident when happened
D．when happened the accident
真空断路器的灭弧室是在高真空状态下工作，其击穿电压比常压下的空气、SF6气体、变压器油的击穿场强高得多。（）
