为了满足清管球在管线内运行时的密封要求，清管球内径应稍大于输气管内径，其过盈量在球未充水时为管线内径的（）%。
A.5
B.4
C.3
D.2
参考答案：D
Is this hotel _____ offered you a job ______ you stayed the first time you arrived here?
A．which; where
B．the one; in which
C．where; that
D．the one that; where
粗刮、细刮、精刮在研点数上有何不同？
