阅读短文，选择正确的答案，将序号填在括号里。

      Hello, I'm David. I have two new teachers, a math teacher and a computer teacher. Do you know them?

Mr. Brown is my math teacher. He is from England. He is strict, but' he is kind. He is strong. He is a good

football player. His class is so much fun! My computer teacher is Miss Li. She is short. She is pretty. She's

very kind, too. I like them very much.

1. How many new teachers does David have?[ ]

A. Two.

B. Three.

C. One.

2. Who is David's math teacher?[ ]

A. Miss Brown.

B. Mr. Brown.

C. Mr. Carter.

3. Does David like his math teacher? [ ]

A. Yes, he does.

B. No, he doesn't.

C. Yes, he is.

4. What is David's computer teacher like?[ ]

A. She is funny and kind.

B. She is short and pretty.

C. She is very strong.

5. Is Miss Li strict?[ ]

A. Yes, she is.

B. No, she isn't.

C. No, she doesn't.

“在水中能下沉的物体是否受到浮力呢？”小明决定通过实验探究．他取了一个重为1N的铝块，挂在弹簧测力计上，当铝块浸没在水中时，弹簧测力计的示数为0.63N．依据小明的实验可知铝块受到了水的浮力作用，且铝块所受的浮力大小为______N．接下来，小明又做了进一步的探究，他让浸没在水中的铝块处在不同的深度，然后观察弹簧测力计的示数是否变化，小明的设计是想探究______．