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问题 解答题
用较为简便的方法计算下列各题：
（1）3-（+63）-（-259）-（-41）；
（2）(2
1
3
)-(+10
1
3
)+(-8
1
5
)-(+3
2
5
)；
（3）598-12
4
5
-31
3
5
-84
（4）-8721+53
19
21
-1279+43
2
21
．
答案

（1）原式=3-63+259+41=-60+300=240；

（2）原式=2

1
3
-10
1
3
-8
1
5
-3
2
5
=-8-11
3
5
=-19
3
5
；

（3）原式=598-84-（12

4
5
+3
3
5
）=514-16
2
5
=497
3
5
；

（4）原式=（-8721-1279）+（53

19
21
+4
2
21
）=-10000+58=-9942．

问答题

(B)


Directions: Translate the following passage into Chinese.
Monitor your body language to make sure you don’t seem too desperate for the job, or too eager to please. Keep a poker face in business situations. Inappropriate smiling is the most common example of a nonverbal behavior that undercuts verbal messages—making you appear weak and unassertive. Good eye contact is also important. One study found that job applicants who make more eye contact are perceived as more alert, dependable, confident and responsible.
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单项选择题

采用点位控制的数控机床有( )。

A．数控铣床
B．数控车床
C．数控镗床
D．数控磨床
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