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问题 单项选择题 A1型题

在进行临床试验设计时，允许犯第二类错误的概率最大值是取（）

A.β=0.01

B.β=0.05

C.β=0.10

D.β=0.20

E.β=0.25

答案

参考答案：D

阅读理解

                                  SUNSHINE COMPANY
Products for a Safe Environment
A4277—HAND SOAP
You are going to love this natural soap. There are no chemicals in it. It is very good for your hands and face.
D4545—GARDEN SPRAY
Insects are going to run away from our new chili garlic spray. It is safe and natural.
B2377—HOME CLEANER
You are not going to need 5 or 6 chemical cleaners. You have Dr Clean! It is safe and strong, and it cleans everything in your house!
A2104—CANVAS BAG
You are going to say, “ No paper or plastic!” You have this excellent heavy canvas shopping bag.
 

Item
Code
Price
Natural shampoo
T6762
$3.00
Garden spray
D4545
$2.50
Canvas bag
A2104
$4.00
Hand soap
A4277
$1.00
Home cleaner
B2377
$2.25
Postage: $3.50
50. Dr clean is _______.
A. an expert in cleaning everything                    B. a newly—invented machine
C. a can of cleaning powder                       D. a magic cloth for cleaning
51.According to the ads, where can you mail your letter to if you want something to kill ants?
A. D4545 Garden Spray                             B. Sunshine Company
C. Safe Environment Product                            D. The Dr Clean’s
52.According to the ads. How much do you have to pay for three shampoos and two canvas bags 
totally?
A. $ 12.25                           B. $ 20.50                    C. $ 13.50                    D. $ 17.00
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多项选择题

提高干熄焦的防爆性，可采取（）。

A、往系统内充入蒸汽

B、往系统内充入氮气

C、增开常用放散阀，提高预存段压力

D、导入空气烧掉可燃气体
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