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问题 解答题
通过实验知道如果物体的初始温度是θ1℃，环境温度是θ0℃，则经过时间t分钟后，物体温度θ将满足：θ=θ0+（θ1-θ0）•2-kt
，其中k为正常数．
已知一杯开水（100℃）在室温为20℃的环境下经过30分钟后温度会降至30℃．
（1）若当前室温为16℃，从冰柜中拿出的温度为-4℃的冰块，经过5分钟之后，能否融化？（即温度达到0℃以上，参考数据：
2
≈1.414）
（2）在室温为-4℃的环境下，12℃的水经过多长时间可以结冰？-20℃的冰能否融化？（即变为0℃，请依据本题的原理解释）
（3）探究：同样多的一杯开水和一杯冷水一同放进冰箱，哪个先结冰？请猜想答案，有条件的在考后抽空做实验并上网查阅相关资料．
答案

依题意开水（100℃）在室温20℃的环境下，经过30分钟后温度降至30℃．

故30=20+（100-20）•2-k•30⇒k=

1
10
（2分） 

∴θ=θ0+（θ1-θ0）•2-

t
10
…（3分）

（1）θ=16+（-4-16）•2-

5
10
=16-20×
2
2
≈1.86℃＞0℃…（6分）     

∴5分钟之后，这个冰块能融化．…（7分）

（2）12℃的水结冰：0=-4+（12-（-4））•2-

t1
10
⇒t1=20分钟…（9分）

-20℃的冰融化：0=-（-20-（-4））•2-

t2
10
：⇒t2不存在（11分）

∴-20℃的冰在-4℃的条件下不可能融化．…（12分）    

（3）开水先结冰（详见“姆潘巴的问题”）．（14分）

单项选择题 A2型题

患者男，42岁。既往体健，近来反复出现阵发性呼吸困难，被迫坐起，坐起后呼吸困难减轻，查体双肺满布哮鸣音。考虑最可能的诊断是（）

A.慢性喘息型支气管炎

B.支气管哮喘

C.慢性阻塞性肺疾病

D.支气管肺癌

E.心源性哮喘
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选择题

Every year Chris Brogan posts his three words for a new year. many others and I have followed his lead for the past three or four years. They helped me a lot. My words for last year were “passion”, “focus” and “delegate” and I stayed true to them. This year, 2013, my goals are more personal and less professional.

FOCUS

Focus is making a repeat appearance on my list this year because I’m too much of a multitasker. The problem is that I have trouble finishing one thing with so many things calling me. When I was working as a writer, all my projects were handled via a schedule, I’m putting a fitness and housekeeping routine into my schedule.

HEALTH

I get so busy taking care of everyone else, and I forget to take care of myself and this has to change. My health suffers and my weight suffers. I have to get my health in check , not only for me but because I promised my 9-year-old son. I’ll make good food and lifestyle choices. I miss being thin, and it’s time to get it back.

CELEBRATE

What good is having it if I’m not taking time to enjoy it? I have a wonderful job, a happy family, and so much to be thankful for. So how come I spend all my time working? Last summer my family took our first vacation in four years, the best thing I’ve done for myself and my family in a long time. This year, I’m making sure to take time to enjoy life and celebrate its many blessings.

Do you have any words for 2013?

小题1:The underlined word “multitasker” probably refers to a person who          .

A．makes a living by writing

B．always fails to finish a task on time

C．has several things to do at the same time

D．pays more attention to fitness and housekeeping小题2:Why does the writer have “HEALTH” as one of his three words?

A．He wants to take better care of others.

B．He’s gaining weight and feeling bad.

C．He did not take any exercise in the past.

D．He got the idea from his son.小题3:What can we learn from the passage?

A．The word “CELEBRATE” can remind the writer to enjoy life.

B．The writer has a vacation with his family every four years.

C．The word “FOCUS” can help the writer focus on his family.

D．The writer used to be overweight for lack of exercise.小题4:The best title for the passage might be      .

A．Three Words for 2013

B．Health Should Go First

C．Keep Organized

D．Goals for 2013
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