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问题 选择题

一个灯泡的灯丝烧断了，把断了的灯丝搭在一起，接在原来的电源上，灯泡会更亮（灯丝电阻为R，通过的电流为I，两端的电压为U，消耗的功率为P）。产生这种现象的原因是：[ ]

A.R变大，I不变；由P=I2R可知，P变大

B.R变小，I变小；由P=I2R可知，P变小

C.R变大，I变大；由P=UI可知，P变大

D.R变小，U不变；由P=可知，P变大

答案

答案：D

补全对话，情景问答
根据对话情景选择恰当的选项，其中有两项是多余的。
A. I'm sorry to hear that.
B. I hope everything goes well.
C. Your uncle telephoned.
D. Everything is ready.
E. Not so well.
F. He feels very lonely.
G. He has a bad cold.
Mother: Lin Tao, are you setting the table for your grandparents and uncle?
Lin Tao: Yes, Mom. 1.            
Mother: Just set two places. 2.            He said he wasn't able to come.
Lin Tao: What's the matter with him?
Mother: 3.           
Lin Tao: 4.            Did my uncle sound worried?
Mother: Yes. He said he would go to see a doctor.
Lin Tao: 5.            I will ring him up.
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多项选择题

定点生产企业可以将第二类精神药品制剂销售给（）

A.全国性批发企业、区域性批发企业

B.专门从事第二类精神药品批发业务的企业

C.医疗机构

D.第二类精神药品零售连锁企业
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