W: I‘ m terribly sorry I‘ m late. I had rather a difficult time finding your office.
M:__________
A. Saying sorry won" t be enough for being late. You have to account for what you" ve done.
B. That" s all right. Please sit down and I" 11 start to ask you a few questions.
C. You needn" t saying sorry. It" s often the case.
D. Put on your name in the attendance record and go to your work.
查看答案
通过增大入射光的波长，可提高分子吸光光度分析法的灵敏度。
AAS分析中，消除电离干扰的方法就是在试液中加入适量难以电离的其他元素。
在反向市场上，由于对现货及近期月份合约需求迫切，购买者愿意承担全部持仓费来持有现货。（）
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