试题与答案

2010年10月我国海南省连续遭遇暴雨袭击,万泉河河水泛滥,救灾人员需要驾驶冲锋

题型:多选题

题目:

2010年10月我国海南省连续遭遇暴雨袭击,万泉河河水泛滥,救灾人员需要驾驶冲锋舟渡过万泉河进行救援,设河水流速4m/s,冲锋舟相对于静水的速度为10m/s,假设河岸为直线,河宽约为500m,若救援人员要在最短的时间内过河,则(  )

A.冲锋舟渡河最短的时间约为50s

B.冲锋舟渡河最短的时间约为36s

C.冲锋舟在出发点下游200m处到达对岸

D.冲锋舟在出发点正对面靠岸

答案:

当静水速与河岸垂直时,渡河时间最短,t=

d
v
=
500
10
s=50s.沿河岸方向上的位移x=vt=4×50m=200m.故A、C正确,B、D错误.

故选AC.

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题型:阅读理解

阅读理解。

     Preparing for a medical emergency involving your pet is always best accomplished before the event takes place. This series is designed to help guide you through the important decisions about first aid, as well as how and when to transport your pet quickly and safely to a veterinary hospital or emergency ability.

     VeterinaryPartner.com has provided this complete reference book online for you to skim through, expanding your knowledge of dog and cat first aid.However, we encourage you to buy the book to keep in your home or car as a quick reference during an emergency.

      This book is an emergency preparedness readyreference for dogs and cats. Wise preventive measures, intelligent use of first aid principles, coupled with recognition of abnormal symptoms and treatment of disorders, diseases, and problems, lead to effective health care.

      A working knowledge of this information will help you get rid of some potentially dangerous circumstances and help you prepare for emergency situations.

      It includes information on what to do and what not to do in specific emergency situations. The authors encourage careful reading and occasional rereading. We have tried to make this book easy to understand, avoiding technical terms as often as possible, but defining them in context when they are necessary.

1.What's the purpose of this passage?

A.To introduce a book, a reference about first aid for dogs and cats.

B.To introduce a website.

C.To introduce a working knowledge.

D.To encourage careful reading.

2.Why are we advised to buy the book?

A.Because it's very cheap.

B.Because it contains a working knowledge of information about dogs and cats.

C.Because it contains information on specific emergency situations.

D.Because you can keep it at hand and find knowledge of dog or cat first aid in case of an emergency.

3.Which is NOT true about the book?

A.It can enlarge the readers' knowledge of dog and cat first aid.

B.It contains the knowledge of recognition of abnormal symptoms of dogs and cats.

C.Although it contains possible technical terms, it is easy to understand.

D.You can read it on VeterinaryPartner.com.

4.What does the underlined word "veterinary" mean in Paragraph 1?

A.应急的  

B.兽医的  

C.紧急的  

D.资助的

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