航煤过滤器滤芯多长时间更换一次？

均相EIA主要通过__________同抗体结合形成__________的免疫复合物，改变了标记酶的活性，通过催化______反应，测定酶活性变化，即可推算出被测样品中待测_______的方法。

Most people have jobs. They go to work nearly every day. Some people are lucky, because they have very interesting jobs. Some people must take a long time to learn how to do their jobs. For example, to be a doctor, one should study for at least five years.

Some young people have very interesting and high-paying jobs. Many young athletes are very successful. Football and tennis players are usually under 35 years old, for older people can’t play these sports very well. They can’t move fast enough. Golf, however, is a good sport for older people. Many golf players are quite old, but they can still play golf very well.

Most people work until they are about 60 years old. Then they retire and have a lot of free time. Some people never retire. These people usually have interesting jobs. Writers, artists, scientists and actors usually work till they are very old.

根据短文内容，选择正确答案。

小题1:One should study for at least _________ years to be a doctor.

A．three

B．four

C．five

D．six小题2:Which sport can old people play?

A．Football.

B．Tennis.

C．Basketball.

D．Golf.小题3:What does the underlined word “retire” mean in Chinese?

A．锻炼

B．学习

C．退休

D．养老小题4:Which of the following is NOT true?

A．Some people have interesting jobs, but some don’t.

B．People usually stop working when they are about 60 years old.

C．Football and tennis players can work as long as they like.

D．According to the passage, writers, artists and doctors have interesting jobs.小题5:What is the passage mainly about?

A．Good jobs.

B．Interesting jobs.

C．Different jobs.

D．High-paying jobs.

用自来水养金鱼时，通常先将自来水经日晒一段时间后，再注入鱼缸，其目的是[ ]

A. 利用紫外线杀死水中的细菌

B. 提高水温，有利于金鱼生长

C. 增加水中氧气的含量

D. 促使水中的次氯酸分解

课堂教学中，教师应把语速控制在（）。

A.每分钟100字以下

B.每分钟100-150字

C.每分钟150-200字

D.每分钟200字以上

B公司全年利润总额为3000000元，其中包括国债利息收入60000元，全年实发工资为900000元。以银行存款实际缴纳所得税费用500000元。
要求：