已知两圆的半径分别为3cm和2cm,圆心距为5cm,则两圆的位置关系是( )A

题型:选择题

问题:

已知两圆的半径分别为3cm和2cm,圆心距为5cm,则两圆的位置关系是(   )
A、外离
B、相交
C、外切
D、内切
考点:圆和圆的位置关系(圆和圆的相离,圆与圆的相交,圆与圆的相切)
题型:选择题

根据短文内容及所给首字母提示写出所缺单词。

    Some western countries insist that China is one of the world's biggest greenhouse gas emitters (温室气体

排放者). But in fact our government has taken actions a   1    to struggle with climate change.

    Firstly, the public are educated to p   2    more attention to the environment. As the government expects,

the people have reached a very h   3    level of knowing low-carbon economy (低碳经济). I   4    you watch

TV, listen to the radio or read newspapers, you'll find low-carbon lifestyle has become a fashion. Secondly,

developing renewable energy is another action. The government is b   5    many wind farms and solar power

stations in the deserts. Of course, w   6    a long time, China will continue using the coal. At the same time,

the government has been making l   7    to punish those people who dare to destroy the environment. Besides,

some s   8    have suggested that greening the deserts is more important than developing new forms of energy.

Their l   9    research shows that 80% of the CO2 in the atmosphere comes from land-use.

    As we know, China hasn't a  10   a balance between the green lifestyle and the economic growth, but we

are on the way. We'll take more actions to reduce the greenhouse gas emission.

1_________ 2_________ 3_________ 4_________ 5_________

6_________ 7_________ 8_________ 9_________ 10_________

题型:选择题
某商场购进一批单价为5元的日用商品.如果以单价7元销售,每天可售出160件.根据销售经验,提高销售单价会导致销售量的减少,即销售单价每提高1元,销售量每天就相应减少20件。设这种商品的销售单价为x元,商品每天销售这种商品所获得的利润为y元.
(1)给定x的一些值,请计算y的一些值.(每空1分,共4分)
x

7
8
9
10
11

y

320
 
 
 
 

(2)求y与x之间的函数关系式及自变量x的取值范围;(4分)
(3)请探索:当商品的销售单价定为多少元时,该商店销售这种商品获得的利润最大?这时每天销售的商品是多少件?(4分)
x

7
8
9
10
11

y

320
420
480
500
480

题型:选择题

患者,男性,63岁,症见吞咽梗阻,食不得下,食入即吐,胸膈疼痛,面色暗黑,形体消瘦,吐下物如赤豆汁,便黑干结,舌红少津,脉细涩,治宜().

A.血府逐瘀汤

B.通幽汤

C.启膈散

D.沙参麦冬汤

E.左归丸

题型:选择题

在事故调查过程中出现那些情况应该从严处理?

题型:选择题

以治疗前后量表SCL-90总分的改变来反映疗效,其评估标准是减分率≥25%为有效,减分率≥( )为显效。

A.70%
B.75%
C.35%
D.50%

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