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问题 填空题
直线ρ=
3
2cosθ+sinθ
与直线l关于直线θ=
n
4
（ρ∈R）对称，则l的极坐标方程是______．
答案

将原极坐标方程ρ=

3
2cosθ+sinθ
，化为：

2ρcosθ+ρsinθ=3，

化成直角坐标方程为：2x+y=3，

它关于直线y=x（即θ=

π
4
）对称的圆的方程是

x+2y=3，其极坐标方程为：ρ=

3
2sinθ+cosθ
．

故答案为：ρ=

3
2sinθ+cosθ
．

阅读理解

An English traveler found himself in a northern European country with a little money to buy the ticket for the travel back home. As he knew that it would take him only two days to get to England, he thought that he would be all right without food. So he bought a ticket and went on board. He closed his ears to the lunch bell. When dinner time came, he refused to go to the dining hall, saying that he was not feeling well. The next morning, he didn’t go to breakfast and at lunch time he again stayed in his room. At dinner time he was so hungry that he could not stand it any longer. “I’m going to eat, ” he said, “even if they throw me into the sea. ” At dinner he ate everything in front of him at the table, then he worried about the coming trouble. “Bring me the bill,” he said. “there isn’t any bill. ” Was the answer. “On the ship the money for the ticket includes meals. ” The traveler regretted when he heard this.

根据短文内容选择正确答案。

小题1:The English traveler knew he would ________ in two days.

A．be back home

B．buy some food to eat

C．travel everywhere in Europe

D．enjoy himself in the ship小题2:The first day he _________ to have lunch and dinner.

A．stole

B．sold

C．refused

D．missed小题3:He didn’t go to the dining hall because __________.

A．he was ill

B．he was not feeling well

C．he was not hungry

D．he had no money小题4:The next day he decided to ________ at last.

A．stay in his room

B．be thrown into the sea

C．have dinner

D．run away小题5:The English traveler _________ that he had no meal on the first day.

A．was excited

B．was sad

C．was glad

D．was told
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单项选择题

灾害性预警信号由谁发布？（）

A.气象部门所属的气象台站

B.当地人民政府

C.防洪抢险部门

D.新闻媒体
查看答案