题目内容

在有瓦斯矿井爆破时，要选用与瓦斯等级相应的煤矿许用爆破器材,其起爆总延期时间不得超过()。
A 100ms
B 130ms
C 1000ms
D 1300ms

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井下爆破装药时，每个炮孔同时操作人员不应超过()，严禁向炮孔内投掷起爆体和受冲击易爆的炸药。
A 1人
B 2人
C 3人
D 4人

马头门的爆破应遵循“少钻眼，多装药”的原则。()

Part A
You have read the following newspaper advertisement in which a restaurant wants to employ a cashier, and you want to get that job.
Cashier Bilingual in English & Chinese
Female, aged 20 - 40
Flex. hrs, with a total of 40 a week
Salary: $ 8 per hour
Write to Wang Li
Address: No. 1147N, New York Street
Hong Kong Restaurant
Write a letter to him, tell him about:
1. your English level and your age
2. your present circumstances
3. the reasons of why you want to get the job
You should write approximately 100 words. Do not sign your own name at the end of your letter. Use" Chang Hua" instead. You do not need to write the address.

一位小学数学教师教学"千克的初步认识"时，在用教具一天平来称粉笔时，忘了拆下天平物盘下的胶垫，出现了第一次称一支粉笔为100克，第二次称一支粉笔为10克。而该老师把两次测量10倍之差向学生解释是天平这种测量工具的误差。假如你是这位老师，你会用什么方法来解决？