在实验室出现紧急情况时,立即去查看实验室消防疏散通道,以便安全离开现场。
查看答案
对于有害废弃物不得直接倒入下水道或生活垃圾箱中,应置于指定地点,封闭完全,即可长时间存放。
A. 对
B. 错
—________ is the sweater?—It's twenty dollars.
A. How many
B. How long
C. How much
D. How often
—What about these socks?—________ two dollars.
A. It's
B. They're
C. These are
D. Those are
—I like big hats. ________？—Yes, I have this one here.
A. It's five dollars
B. Can I help you
C. How can I do for you
Do you have one
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