如图所示，理想变压器原副线圈匝数之比为4：1，原线圈接入一电压为u=220sin

关于机载交通防撞和警告系统TCAS说法正确的是（）.

A、评估本机与相遇飞机发生危险接近的可能

B、以S模式应答机为基础而工作

C、能提供语音提示信息和视觉信息

D、以上都对

选择正确的替换词。

1. We have been friends for ten years.

A. since ten years              

B.ten years ago

C. since ten years ago          

D.ever since

2.I waited here for one and a half hours.

A. an hour and a half  

B. an hour and half  

C. half an hour  

D. a half and one hour

3. I have been collecting stamps for several years.

A. a little    

B. many      

C. much      

D. a few

4. More than twenty students come to school on foot in our class.

A. Less than    

B. Much than  

C. Over        

D. Around

5. Mom stores all the meat in the fridge , or it will go bad.

A. keeps      

B. lies        

C. has        

D. collects

具有泻下攻积、润燥软坚、清热消肿功效的药物是（）

A.大黄

B.甘遂

C.芒硝

D.番泻叶

E.郁李仁

电动冷却水温度控制系统的输出执行装置保护环节不包括（）。

A.三通阀限位开关

B.电源保险丝

C.正反转接触器连锁

D.电机过载保护

刺激心交感神经

A．使心脏起步点细胞的舒张期去极化速率增加
B．使心功能曲线(纵坐标为心缩力或心室搏功，横坐标为心舒末期容积)右移
C．使心肌的β受体激活
D．引起心缩力加强