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问题 单项选择题

已知等成本曲线与等产量曲线既不相交也不相切，此时，要达到等产量线所表示的产出水平，应该（）。

A.增加投入

B.保持原投入不变

C.减少投入

D.或A或B

答案

参考答案：A

阅读理解

阅读理解。

     We can see a picture of a classroom. It is our classroom. It's small. We have 25 students in our class.

The walls (墙) are white and the desks and chairs are new. On the wall there is (有) a flag (旗子) and a clock.

There is a map of China, too. Some plants are on the desk They are for our teacher, Miss Smith. She likes her

students. She comes to school early.

1. Our classroom is _______.

A. big

B. small

C. old

D. interesting

2. We have _______ students in our class.

A. thirty

B. fifteen

C. twenty-five

D. forty

3. _______ are one the wall.

A. A flag

B. A clock

C. A flag and a clock

D. A watch

4. _______ are on the desk.

A. Some books

B. Some plants

C. Some pens

D. Some plants

5. Our teacher is _______.

A. Miss Smith

B. Mr. Smith

C. Mrs. Smith

D. Smith Teacher

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单项选择题

类风湿性关节炎在神经学方面的表现（）

A.很少见

B.常因关节肿胀压迫神经而造成神经学的表现

C.只发生于上肢

D.是神经的压迫性损害

E.脊髓受侵多于周围神经
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