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问题 单项选择题

下列有关可编程调节器所具有的基本功能，正确的是（）。

A.可以实现传统模拟调节器难以实现的多种高级控制

B.通过较易掌握的编程，构成所需的控制功能，既方便又灵活

C.有自诊断和通讯功能

D.以上都正确

答案

参考答案：D

阅读理解

阅读理解。

1. You can use the facilities in the Shine Sports Centre at _____.

A. 9 am on Sunday

B. 5 pm on Wednesday

C. 7 am on Thursday

D. 9 am on Saturday 

2. You and your classmate have to spend _____ on the membership card for two years.

A. $10

B. $20

C. $30

D. $40

3. What does the underlined (划线的) word "book"mean in Chinese?

A. 书

B. 账册

C. 预定

D. 记录

4. Which of the following is TRUE?

A. A1l people have the chance to be members of the Centre.

B. You call get the membership card at 6 o'clock in the morning.

C. You can't book the facilities over the telephone.

D. You don't need to bring the membership card when you need to use the facilities.

5. Who is the advertisement written for?

A. Young people.

B. Old people.

C. Couples.

D. Little kids.
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选择题

在K2CO3样品中含Na2CO3、KNO3、Ba(NO3)2中的一或二种杂质．将13.8 g该样品溶于足量水中得到澄清溶液，再加入过量CaCl2溶液，可得9.0 g沉淀，则原样品中含有的杂质会是（　）

A．肯定有Na2CO3，没有Ba(NO3)2

B．肯定有KNO3，没有Ba(NO3)2，可能还有Na2CO3

C．肯定没有Na2CO3，Ba(NO3)2

D．无法判断何种为肯定或否定的杂质
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