在程序中不需要用public等命令明确声明和建立，可直接使用的内存变量是（ ）。

When you are ill, you must be unhappy because your body becomes hot, and there are pains all over. You don’t want to work. You stay in bed, feeling terrible.

What makes you ill? They are germs. Germs are everywhere. They are very small and you can’t see them with your eyes, but you can find them with a microscope（显微镜）. They are very small and there could be lots of them on or in a very small thing.

Germs are always in the dirty water. When you look at dirty water under a microscope, you will see them in it. So your parents will not let you drink dirty water.

People can also find germs in the air and dust. If you cut your finger, and if some of the dust goes into the finger, it will become big and red, and you will have much pain. Sometimes they will go into your body and you will have pain everywhere.

根据文章的内容选择最佳答案。

小题1:The write thinks that you’ll __________ when you are ill.

A. not want to work  B. not feel happy  C . A and B

小题2:You can see germs __________.

A. when you are ill

B. when you use a microscope

C. when you cut your finger

小题3: A Microscope is used for __________.

A. making very big things look much smaller

B. making very small things look much bigger

C. examining body

小题4:Which sentence is not right according to the passage?

A. There may be lots of germs on a small thing.

B. If germs go into your body, you will have pain everywhere.

C. We can see germs with our own eyes.

小题5: The writer talks about __________.

A. what makes you ill

B. how to take care of your fingers

C. how to find germs

如上图，三个完全相同的金属小球a、b、c位于等边三角形的三个顶点上。a带负电，b和c带正电，a所带电量大小比b的要大。已知c受到a和b的静电力的合力可用图中四条有向线段中的一条来表示，那么它应是（       ）

A．F₁

B．F₂

C．F₃

D．F₄

电气安全检查一般每季度（）次。

一条计算机指令中，规定其执行功能的部分称为( )。

A．源地址码

B．操作码

C．目标地址码

D．数据码