Eugene's never willing to alter any of his opinions. It's no use _____ with him.[ ]

A. to argue

B. arguing

C. argued

D. having argued

塑料给水系统应在试验压力下稳压1h，然后在工作压力的1.15倍状态下稳压（），压力降不得超过0.03MPa，同时检查各连接处不得渗漏。

A、0.5h

B、1h

C、2h

D、2.5h