如果掺混空气系统故障，区域控制器辅助通道将区域温度调节到：（）.A.24℃ B.18

猜谜语：（1）2、4、6、8、10（打一成语）（    ）；

（2）清仓大甩卖（打一数学名词）（    ）

某兴趣小组用足量10%稀盐酸分别与下列四种物质反应，制取500mL（通常状况下）CO₂气体，下列固体中所需质量最多的是（　　）

A．小苏打（NaHCO₃）

B．纯碱（Na₂CO₃）

C．碳酸钙

D．草木灰（主要成分是K₂CO₃）

某人在河岸上，借助岸边的大树，利用滑轮组通过拉绳使停泊在水中的船匀速靠岸．已知滑轮组是由一个定滑轮和两个动滑轮组成的（滑轮和拉绳自重不计），船的总质量为7.92×10³kg，船匀速移动时受到水的阻力是船重的0.01倍，船受到滑轮组的拉力与人拉绳子的力始终水平，若人的拉力是220N，船靠岸的速度是0.3m/s，（g=10N/kg）

求：

（1）滑轮组的机械效率．

（2）人拉绳的功率．

以下物流活动中不存在约束关系的是（）。

A.运输与库存 

B.顾客服务水平与物流成本 

C.生产物流与销售物流 

D.提高供货率与增加库存

An old man visited a new doctor. He was very young. "I don’t feel well, doctor," he said, "Please find out what’s wrong with me."
"Take off your clothes and lie on the bed," the young doctor said, "I’ll examine you." The old man took off his clothes and lay down on the bed, and the young doctor examined him.
However, he couldn’t find anything wrong with the old man. He listened to his heart. He looked into his throat. He examined every part of him. At last he said, "I’m sorry, but I can’t find anything wrong with you. You’re as healthy as I am." "That’s very strange," the old man said, "because I feel really bad."
"Come back tomorrow and see me again if you don’t feel better." The young doctor said, "I’ll examine you again." "All right, doctor," the old man said. Slowly, he stood up and put on his clothes. Then he walked out of the hospital.

Who visited the new doctor
A. A young man. B. An old man. C. A young girl.

A few seconds later, the doctor’s nurse ran in. "Doctor! Doctor!" she cried. "That man you said was healthy has just died outside the door." The doctor thought quickly, "Then turn the body around so that people will think he was coming in," he said.