纤维损伤有几种情况，如何合理选择给棉板的分梳工艺长度？

阅读理解。

     When David left college, he went to Australia. When he returned to England for a visit twenty years

 later, he decided to go back to his old college.  David was very glad when he found out that his old

 college teacher was still teaching there. He went to visit the old man,  and after they had an interesting

 talk,  the teacher went out to get something. While he was away, David saw an exam paper on the

 desk. He looked at the date on it and saw that it was given to the student a week ago. David picked the

 paper up and read it.

     When the teacher came back, David said to him, "Mr. Smith, I'm sure that these are exactly the same

 questions that you asked us in our exams twenty years ago! How is that possible?"

     "Yes, that's right," agreed the teacher. The questions are the same,   but the answers have changed."

1. David went to _____  after he left college.

    A. England                

    B. Australia

    C. another college        

    D. his teacher's office

2. David felt _____ when he found out that his college teacher was still teaching there.

    A. worried                

    B. sorry

    C. amazed                  

    D. happy

3. The students took the same exam _____.

    A. as David did twenty years ago

    B. when David' s teacher was away

    C. as David did a week ago

    D. when David read the paper

4. Can you guess why the teacher still used the same exam paper twenty years later?

    A. Times have changed, answers should change, too.

    B. Different students have different answers.

    C. The teacher tried to find an excuse for his being lazy.

    D. The exam paper was done by David and his classmates 20 years ago.

行业发票适用于()。

A．商业零售统一发票

B．商业批发统一发票

C．工业企业产品销售统一发票

D．广告费用结算发票

药品质量标准中的检查项内容不包括（）

A.均一性检查

B.物理常数检查

C.有效性检查

D.安全性检查

利民农用品商店运来一批化肥，如果每天卖出25袋，这批化肥24天可以卖完。如果每天卖出30袋，这批化肥多少天可以卖完？如果每天卖出24袋呢？20袋呢？

铁路局的工作量等于（）

A.使用车数

B.卸空车数

C.接入重车数

D.使用车数与接入重车数之和