下列各句中划线词语使用不准确的一项是

How do you deal with the disagreement between the company and the customers? — The key ____ the problem is to meet the demand ____ by the customers. [ ]

下列各句中，标点符号使用正确的一项是( )

Mrs. Green will not be able to come for dinner tonight because ______ then.

days, we _____ for our final exams.