载玻片和盖玻片在清洗前可先在（）溶洗中浸泡1h。A、2％的盐酸 B、8％盐酸 C、2％的

Read and answer the questions. （阅读短文，并回答问题） 

     This is a room in Joan's house. There is a bed, a table and some

chairs in it. There is a glass and some books on the table. Joan is in

the room.  Her father and mother are in the school. They are teachers.

They work hard.

Write "T" or "F".

( )1. There is no table in Joan's room.

( )2. There is a glass and some books on the table.

( )3. Joan's parents are in the room.

Read and choose.  

4. Do Joan's parents work hard?                 

A. Yes, they do.            

B. No, they don't.

C. Yes, there are.            

D. No, there aren't.

若矩形的一条对角线与一边的夹角是40°，则两条对角线相交所成的锐角是______．

下面数中，只读一个零的是（　　）

A．509800

B．7400380

C．7203807060

D．405000003000

4G全国套餐存费送费合约与3G套餐存费送费保持一致（）

蓝牙遥控装置可以形成（）的连接。

A、点到点

B、一点到多点

C、多点到一点

D、多点到多点