题目

I was twenty years old, and my parents were looking forward to the day when I would be earning my own living. Unfortunately, I had absolutely no idea what I wanted my future occupation to be. The only thing I did know was that I did not want to spend the next 45 years teaching, being a nurse or sitting in an office.But that was before the postman delivered a catalogue (目录) of courses that were being offered at the local college. As I looked through it, I was attracted by a page that talked about the difficulties faced by deaf people in their everyday lives and how students could help by le甲为探究并联电路电流规律的实验电路图．（1）若要测量干路电流，则电流表应串联在甲图中的 处（选填“A”、“B”或“C”）（2）若要测量A处的电流，在连接电路闭合开关前，发现电流表指针位置如图乙所示，调整正确后闭合开关，发现指针又偏向图乙位置，其原因是 ． 位置ABC电流（A）0.180.180.36（3）纠正（2）中错误后，测出A、B、C三处的电流值如上表，由此得出结论：并联电路中，干路电流等于各支路电流之和，且各支路的电流相等，这个实验在设计方案上还存在的不足之处是： ．（写出一条）