阅读，回答问题

       Mr. Green works in a shop. The shop sells，cleans and repairs（修理）hearing-aids（助听器）. One day an old man comes in and puts one down in front of him without（没有）a word. 

       “What’s the matter with it? ”Mr. Green says. The man doesn’t answer. Of course Mr. Green

thinks the man must be deaf（聋的）and something must be wrong with his hearing-aids（听力），so

he says again，more loudly，“What’s wrong with your hearing-aids，sir? ”Again the man says

nothing. So Mr. Green shouts his question again as loudly as he can.

       The man then takes a pen and a piece of paper and writes，“It’s not necessary to shout when

you’re speaking to me. My ears are as good as yours. This hearing-aid is my wife’s，not mine. I

have got a throat operation（咽喉手术）. I can hear very well，but I can’t speak. ”

1. What does the shop do? 

2. Why does the old man come to the shop ?

3. What’s wrong（什么毛病）with the old man?

某患者，在出差途中，不幸感染急性甲型肝炎在外地住院。他需要将自己生病的情况告诉家人，于是给家里写信。其信件应该用何种方法处理后再寄出

A．高压蒸汽灭菌
B．甲醛熏蒸柜熏蒸
C．氯胺溶液喷雾
D．煮沸消毒法
E．过氧乙酸擦拭