已知等比数列{an}的公比q为正数,且a3•a9=2(a5)2,则q=( ) A.

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问题:

已知等比数列{an}的公比q为正数,且a3a9=2(a5)2,则q=(  )
A.1B.2C.
2
D.
3
考点:等比数列的定义及性质等比数列的通项公式
题型:选择题

阅读理解。

     A four-year-old girl is lying in the arms of a doctor. She has just become motherless. The bombing

(轰炸)destroyed(毁坏)her home and killed her mother.

     Every day we see pictures like this on TVs or in newspapers. We see young Iraqi children begging

for food and water from American and British soldiers as they move through towns and cities towards

the capital, Baghdad(巴格达). We see these children following grown - ups, carrying bags of things

almost at the same size as their small bodies as they flee their homes in Baghdad.

     "Dad, why are the Americans striking(攻击)us? Are we going to be killed?" asks the son of Abu

Sinar, an Iraqi engineer, Abu finds it hard to explain this war to his eight - year- old son.

     He tries to comfort(安慰)him by saying, "The bombs are far away from us. The Americans are

fighting the soldiers. We are going to be all right." Even though Abu knows this isn't always the truth.

But what else can he do? In Baghdad, parents give their children sleeping pills to make them sleep so

that they won't hear the sound of bombing. And all the schools are closed.

     "All we can do is to listen to and hear the war," said Abu. "We, all the people and the children,

have to live in fear. We feel hopeless and helpless. We don't know where the next bombs are going.

We can do nothing but wait to be killed. "

1. During the war, children are ________.

A. studying at school      

B. fighting at the front

C. safer than their parents    

D. in great danger

2. The children have to flee their homes because ________.

A. it is dangerous to stay at home because of the bombing

B. their parents are not at home

C. they want to get food and water

D. they want to welcome the foreign soldiers

3. "Sleeping pills" are ________.

A. a place to keep children safe

B. a kind of thing to help them to be away from the war

C. a kind of medicine to help them to fall asleep

D. a kind of food to make them strong

4. Abu finds it hard to explain this war to his son, because ________.

A. he doesn't want to tell him the real reason

B. he doesn't want to tell a lie

C. he doesn't know how to explain it clearly

D. it isn't good to tell him why

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STCW78/95公约的规则A部分为对船员知识和技能的()

A、指南

B、建议性要求

C、强制性标准

D、最低要求

题型:选择题

亚急性和慢性疾病适合用以上哪一剂量治疗()

A.无热量(Ⅰ级剂量)

B.微热量(Ⅱ级剂量)

C.温热量(Ⅲ级剂量)

D.热量(Ⅳ级剂量)

E.Ⅳ级剂量

题型:选择题

建筑工程质量验收划分的单位工程的观感质量应由验收人员通过现场检查,并应()确认。

A.监理单位

B.施工单位

C.建设单位

D.共同

题型:选择题

山岭隧道的结构防排水施工中,衬砌的( )应采用橡胶止水带或塑料止水带防水,其止水带不得被钉子、钢筋和石子刺破。

A.沉降缝

B.施工缝

C.伸缩缝

D.引水管

E.泄水孔

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