一般情况下问卷应在多长时间内完成，否则会影响应答的效率
A．20分钟
B．30分钟
C．40分钟
D．50分钟
E．1小时
参考答案：C
John: _________
Jack: In two weeks.
John: Are you going to Japan?
Jack: No. I'm going to Australia. I went to Japan two years ago.
A．How long have you been here?
B．When is your holiday?
C．When are you leaving for Australia?
D．How long do you plan to stay here?
在地下水监测项目中，北方盐碱区和沿海受潮汐影响的地区应增测（）项目。
A.电导率、磷酸盐及硅酸盐
B.有机磷、有机氯农药及凯氏氮
C.导电率、溴化物和碘化物等
