假如某薪酬等级中，中间值是3100元，薪酬变动率50%，则起薪点为（）
A.2480元
B.1500元
C.1750元
D.3875元
参考答案：A
The prices _____ up all the time and no one knows when it will become stable. [ ]
A. had gone
B. have been going
C. have gone
D. had been going
泡沫消防炮的性能要求中，泡沫的射程一般都大于或等于（）m。
A、15
B、30
C、45
D、50
