下面有关铸钢件探测条件选择的叙述中哪点是正确的？（）A、探测

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问题单项选择题

下面有关铸钢件探测条件选择的叙述中哪点是正确的？（）

A、探测频率应等于大于5MHz

B、透声性好粘度大的耦合剂

C、晶片尺寸小的探头

D、以上全部

答案

参考答案：B

阅读理解

Learning Computers
This twelve-hour course is for people who need to learn about computers. You will learn what computers
are, what they can and can't do and how to use them.
Course fee(费用) : $ 75
Jan. 4,7,11,14,18,21 Wed. & Sat. 9:00～11:00 a.m.
Zhang Hua is a professor from Beijing University. He has over twenty years of experience in the computer
field.

Typing
This course is for those who want to learn to type. You are tested first and then you can practice at one of
eight different skill levels. This lets you learn at your own speed. Each program lasts 20 hours. Bring your
own paper.
Course fee: $ 125
Two hours each evening for two weeks. New classes begin every two weeks. This course is taught by a
number of professional teachers.

Language Study
Have you already tried to improve your English and failed? Do you want to learn English well? Come and
this three-month course will help you make it.
Course fee: $ 130
Mon. &. Wed. 2:00一5:00 p.m.
All the teachers are from English-speaking countries.

1. If you choose the Learning Computers course, you'll have classes __________.

A. from Monday to Friday
B. on Wednesday and Saturday
C. on January 4,7,12,15
D. in the afternoon every day

2. From the ads we know that Zhang Hua __________.

A. is a teacher from Beijing University
B. has no experience in the computer field
C. can type very well
D. comes from an English-speaking country

3. If you choose the Typing course, you __________.

A. should have a test first
B. needn't bring your own paper
C. can't learn at your own speed
D. should pay $ 115

4. Mr.Black works in the day and only has time in the evening, he can only choose the __________ course.

A. Learning Computers
B. Typing
C. Language Study
D. None of the above

5. The Language Study course will last __________.

A. twelve hours
B. two weeks
C. three months
D. three weeks