保养后上电检查变压器输入电压是否在适当范围（），所使用的保险丝都应该为标准保险丝，严禁用铜丝替代。
参考答案：许电压上下波动7%
下图为某天气系统图，回答1—2题。
1、此时图中[ ]
A．城市被高气压控制，天气晴朗
B．a地大风降温，并可能有降水
C．c地刮西北风
D．b地雨过天晴
2、下图中沿甲乙线所作的天气系统垂直剖面示意图正确的是
A．A
B．B
C．C
D．D
Ten years ago ___ only one building in our school. And in 10 years, ___ five buildings in our school. [ ]
A. there will be, there are
B. there was, there are
C. there was, there will be
D. there will be, there was
