单项选择题：沙漠里的鸵鸟被迫击而无法逃脱时，把头钻入沙滩，危险看不见了也就等于不存在了。对于这种

题型：阅读理解

Bill, Frank and Dave were three brothers. Every year they sent their mother expensive gifts on her birthday,. They liked to show her how rich they were.

The eldest brother. Bill, had a lot of money and he wanted his mother to have the most expensive gifts, but he didn’t know what to buy. So he put an ad in the newspaper. “Wanted－the greatest gift for my mother.”

About a week before his mother’s birthday a man came to his office. He brought a big bird.

“This bird.” the man said, “can speak ten languages and sing some pop songs.”

“Really? I’d like to listen to it,” Bill said.

The man made the bird talk in French and tell a joke in Japanese. Then the bird sang a beautiful song. Bill was very happy and paid nine thousand dollars for the bird. The next day Bill sent the bird to his mother with a birthday card.

The day after his mother’s birthday he called his mother. “Well, mother” he asked, “What do you think of the bird?”

“Oh, it’s very delicious, dear.” said his mother.

小题1:Who is the eldest brother?

A．Dave

B．Bill

C．Jack

D．Frank小题2:What did Bill put in the newspaper?

A．A show

B．A magazine

C．An ad

D．A report小题3:How many languages could the bird speak?

A．Five

B．Seven

C．Fight

D．Ten小题4:How much did Bill pay for the bird?

A．Nine dollars

B．Ten dollars

C．Nine thousand dollars

D．Ten thousand dollars小题5:What did Bill send to his mother for her birthday?

A．A bird with a card

B．Some money

C．A joke

D．A song

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题型：填空题

（理）将极坐标方程ρ=sinθ+2cosθ化为直角坐标方程______．

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题型：单项选择题

拟左甲状腺素替代治疗，最适宜的起始剂量为

A．125ug

B．100ug

C．75ug

D．50ug

E．25ug

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题型：问答题

在地面附近的真空中，存在着竖直向上的匀强电场和垂直电场方向水平向里的匀强磁场，如图甲所示。磁场随时间变化情况如图乙所示．该区域中有一条水平直线MN，D是MN上的一点．在t=O时刻，有一个质量为m、电荷量为+q的小球(可看作质点)，从M点开始沿着水平直线以速度做匀速直线运动，时刻恰好到达N点．经观测发现，小球在t=2至t=3时间内的某一时刻，又竖直向下经过直线MN上的D点，并且以后小球多次水平向右或竖直向下经过D点．求：