TN106二氧化碳测定仪的报警浓度是()。
A、500ppm
B、1000ppm
C、1500ppm
参考答案:B
未在银行开户的个人汇款和办理银行汇票按()收费。
A.1%,最低1元最高50元
B.5‰最低5元最高20元
C.1%最低5元最高20元
D.5‰最低2元最高50元
They were under the()that the company was doing well, but in fact it was in serious trouble.
A.conclusion
B.expression
C.enjoyment
D.illusion