在保护接地系统中，当碰触有电设备外壳，其外壳对地电压与单相短路电流（）。
A.成正比
B.成反比
C.无关
参考答案：A
As we were driving along we saw a good restaurant, so we stopped（）dinner.
A.having
B.to have
C.having been
D.to be had
紫外线能否杀死结核杆菌？
