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问题 解答题

有10件产品，其中有2件次品，从中随机抽取3件，求：

（1）其中恰有1件次品的概率；

（2）至少有一件次品的概率．

答案

（1）所有的取法共有

C310
种，其中恰有1件次品的抽法共有
C12
•
C18
=16种，

故其中恰有1件次品的概率为

16
C310
=
2
15
．

（2）没有次品的抽法有

C28
=28种，故没有次品的概率为
28
C310
=
7
30
，

故至少有一件次品的概率为 1-

7
30
=
23
30
．

单项选择题 A2型题

女性，34岁，因过度劳累及情绪激动有心悸、胸前区不适、心晕及颈部胀满感，并伴有焦虑或恐惧。心电图：心室率常在160～250次／分钟；QRS波群形态和正常窦性的QRS波型一样，间期小于0.10秒；有逆行P波。诊断为室上性心动过速，应首选（）

A.维拉帕米

B.地高辛

C.普萘洛尔

D.胺碘酮

E.奎尼丁
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单项选择题 案例分析题

Wise buying is a positive way in which you can make your money go further. The （）you go about purchasing an article or a service can actually （）you money or can add （）the cost.

Take the （）example of a hairdryer. If you are buying a hairdryer, you might （）that you are making the （）buy if you choose one （）look you like and which is also the cheapest （）price. But when you get it home you may find that it （）twice as long as a more expensive （）to dry your hair. The cost of the electricity plus the cost of your time could well （）your hairdryer the most expensive one of all.

So what principles should you （）when you go out shopping?

If you （）your home, your car or any valuable （）in excellent condition, you’ll be saving money in the long （）

Before you buy a new （）,talk to someone who owns one. If you can, use it or borrow it to check it suits your particular （）

Before you buy an expensive （）,or a service, do check the price and （）is on offer. If possible, choose （）three items or three estimates.

请在第（）处填上正确答案。 查看材料

A.save

B.preserve

C.raise

D.retain
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