给排水管道的接口可以采用橡胶密封圈的有()。2011版没找到

A.球墨铸铁管 

B.钢管 

C.预应力钢筋混凝土管 

D.UPVC管 

E.HDPE管

Young people should be       to believe that all races are equal.

A．looked up

B．brought in

C．brought up

D．looked in