[单选] Because of the close tolerances used in diesel engine fuel oil pumps, a worn plunger requires()
A . grinding the spare plunger to the barrel B . replacing the plunger and the barrel C . highly polishing both the plunger and barrel D . replacing plunger only
上层建筑的作用是什么?
受理贴现及转贴现交易后系统联动登记贴现登记簿。
电液调节系统中转速给定和负荷给定各有什么作用?为什么设置转速给定值形成模块?
什么是甲板室?
碱―石灰烧结法和拜耳法生产氧化铝需要哪些主要原料?
Because of the close tolerances used in diesel engine fuel oil pumps, a worn plunger requires()