题目内容

煤矿井下矿用防爆电气设备外壳的明显处都有在这种场所使用电气设备的特别标志“()”。

A. IP
B. FB
C. dB
D. Ex

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Section A
Directions: This section is to test your ability to understand short dialogues. There are 5 recorded dialogues in it. After each dialogue, there is a recorded question. The dialogues and the questions will be spoken only once. When you hear a question, you should decide on the correct answer from the 4 choices A , B, C, and D.
(1)

A. 6:30.
B. 7:00.
C. 7:15.
D. 7:30.

以下情况不属于突水预兆的是()。

A. 煤层变潮湿、松软
B. 工作面气温升高
C. 有时煤帮出现铁锈色水迹
D. 矿压增大，发生片帮、冒顶及底鼓

某人机系统采用“故障安全”结构设计，当组成单元发生故障时，机器一面报警，一面还能短时运转，这是()。

A. 消极被动式
B. 积极主动式
C. 运行自检式
D. 运行操作式

听力原文：How did the man send the samples？
(15)

A. By post.
By train.
C. By express.
D. By airmail.