如图所示所在通电螺丝管内部中间的小磁针，静止时N极指向右端，则电源的c端为___

Three days ago, the boss of a gold shop received a letter. As he was very busy, the letter was on his desk till dinner time. When he opened it, a $1000 note fell out onto the desk. With the note was a short letter:

Dear sir, I got married forty years ago. Unfortunately, at that time there was a lot of unemployment and I got no job. I was out of work for about six months before I got another one. Of course I was very short of money. I came to your shop to buy a wedding ring one day. The assistant brought some rings for me to have a look, later she was called away for a moment, and then I put one of the rings into my pocket. When she came back, I said I did not know the size of my girlfriend’s finger. So I left the shop with the ring but I didn’t pay for it. My wife died a month ago, and the fact that I never paid for her ring has been on my conscience(让我良心不安)all these years. I always feel guilty about that. At that time the ring cost $100, and I think that is about ten times at today’s price. Now, I am sending you that amount. Yours truly, A customer

  After reading the letter, the boss said,“Well, life is always full of surprise!”
小题1:The boss of the gold shop got a _________ 3 days ago.
A. ring                      B. letter                    C. gold
小题2:The underlined word“unemployment”means“______”in Chinese.
A.辞职                     B.失业                    C.就业
小题3:The ring the customer put into his pocket was __________ 40 years ago.
A.$1000                    B.$10000                 C.$100
小题4:The customer wrote to the boss in order to ________.
A. send the money for the ring      B. say thanks to him       C. return the ring
小题5:Which is NOT wrong according to the passage?
A. The boss opened the letter by himself.
B. The boss didn’t think life was always full of surprise.
C. When the customer’s wife knew the fact, she was annoyed.