颗粒剂分为可溶性颗粒剂和泡腾颗粒剂两种。

______ important thing in life is to have a great aim, and ______ determination to  attain it.

A．An ; 不填

B．A ; the

C．The ; the

D．The ; 不填

下列调查适合作普查的是（　　）

A．了解在校大学生的主要娱乐方式

B．了解宁波市居民对废电池的处理情况

C．日光灯管厂要检测一批灯管的使用寿命

D．对甲型H1N1流感患者的同一车厢乘客进行医学检查

阅读理解。

     It is common and usual to see people freak out when they face challenges in their life. We all pass in

different life problems and challenges. No one is free of life problems. Only a dead man faces no problem. As long as you are alive, challenges are everywhere.

     How do you face problems and challenges in your life? Problems and challenges are the building

blocks of your personality. They make you who you are. Besides, whether what happened in your life

builds or destructs you depends on how you look at it. If you take your problems as troubles, they will be

troubles and may cause destruction. If you take them as constructive tools, you are going to be built up on them.

     Problems are everywhere. No one can avoid them. And they are good too. They open up a different

look and opportunity if you are willing to see. When you face troubles, do not frustrate or freak out. Just

cool yourself to think in a different direction. Think in a positive way. Every problem has its own good as

well as bad sides. Focus on the good one. Look at the bright side.

     Besides, there is always a good person, perhaps your mom or dad, or one of your friends, right beside you who can turn everything into your best if you are willing to turn to them. No matter what happens,

they will be there to help you. Trust them and they will never let you down. All you need to know is that

you are loved wherever you are.

1. What's the meaning of the underlined phrase "freak out" in Paragraph 1 ?

A. feel shy.   

B. stay calm.  

C. keep up.    

D. feel upset.

2. In Paragraph 2, the writer implies that______

A. problems cause troubles  

B. attitude is everything

C. challenges can be avoided  

D. personalities are built on failures

3. According to the last paragraph, when we're in trouble, we _______.

A. can only depend on our parents      

B. are not alone

C. should only believe ourselves        

D. are not confident

4. What's the writer' purpose to write the passage?

A. To encourage.  

B. To compare.  

C. To prove.

D. To explain.

某企业有A、B两个投资项目，两个投资项目的收益率及其概率分布情况如下表所示：

项目实施情况	该种情况出现的概率	投资收益率
		项目A	项目B
好	0.20	15%	20%
一般	0.60	10%	10%
差	0.20	0	-10%

要求：
(1) 计算两个项目的期望投资收益率；
(2) 计算两个项目收益率的标准离差；
(3) 计算两个项目收益率的标准离差率；
(4) 说明应该根据哪个指标比较两个项目的投资风险，并得出结论。

人体内有20多种微量元素，它们的质量总和不到体重的千万分之一，但是对人的健康却起着重要的作用，下列各组元素全部是微量元素的是（）

A.Na K Cl S O

B.F I Fe Zn Cu

C.N H O P C

D.Ge Ca Cu Mg C