核酸分子中百分比含量相对恒定的元素是A．碳( B．氢( C．氧( D．氮( E．磷(

根据短文内容，完成下面的任务。

    What would you do if you had $76 billion? Bill Gates was happy to give a third of it away to charity. He

spends at least $1.2 billion every year helping the poor.

    Bill is the richest, and also the most generous man in the world. He was born on October 28, 1955. (A)

When he was 20, he left university. Two years later he started Microsoft. For 11 years, Bill has been the

world's richest man.

    This year, he again came top with $76 billion. But he is giving away $28 billion to help others. "I'll give

my money back to the world," said the rich man. "Many people still need medicine and care to become

healthier."

    Bill loves helping others just as he loves computers. He always says "super" when he talks about making

people's health better. "(B)The world's health is a lot like solving computer problems. You get smart people

together. You take it on because there has never been an answer before," he said. If you ask him why he

likes giving away his money, he would turn his head and say,"It's because of my mum. She asked me to

do (C)it years ago when I was just a small boss."

1. 将(A)处的句子改为同义句(每空一词)：______ ______ ______ ______ 20, he left university.

2. 将(B)处的句子译成汉语：_________________________________________

3. (C)处的it指的是(用英文回答，不超过5个词)

4. 回答问题：

    When did Bill Gates start Microsoft?

5. 单项选择。

The writer of the passage wants to ______.

A. introduce Microsoft company to us

B. let us know something about charity

C. tell us who is the richest person in the world

D. praise Bill for his help to the poor people

诊断原发性甲减的最灵敏的放射免疫指标是（）。

A.TSH↑

B.T₃↓

C.吸¹³¹I率↓

D.TGAb↑

E.TPO↑

内镜技术用于腹腔脏器探查并称为"腹腔镜检查"始于哪一年

A．1925年

B．1924年

C．1911年

D．1910年

E．1901年

实验室里用下、如图所示装置制取纯净的无水CuCl₂．试回答下列问题：

（1）写出烧瓶中发生反应的化学方程式，并标出电子转移的方向和数目______．

（2）B处盛有饱和食盐水（或水），其作用是______．

（3）C处盛放的试剂______（填名称），其作用是______．

（4）E处盛有______（填名称），发生反应的离子方程式为______．

（5）实验结束时，应先熄灭______处酒精灯．

土壤资源评价的具体方法有（）和（）。