摩尔吸光系数(e)的单位为 ( )
A. mol/(L·cm)
B. L/(mol·cm)
C. mol/(g·cm)
D. g/(mol·cm)
符合朗伯-比尔定律的有色溶液,在不同波长测定的摩尔吸光系数不同。
A. 对
B. 错
The man is worried about Sandra’s ______.
A. way of living
B. attitude towards her work
C. relationship with her colleagues
What does Sandra think of her present job?
A. She doesn’t enjoy it.
B. She finds it difficult.
C. She dislikes it and wants to change it.
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