法定计量检定机构应与顾客或其代表保持沟通与合作,但不允许顾客到实验室监视与其工作有关的操作。
参考答案:错
-Mary,could you please post the letter for me while you are out?
-________
A.I'd rather you didn't.
B.It's OK with me.
C.What for?
D.By all means.
酸碱中和反应是一种复分解反应。()