【单选题】单作用叶片泵、双作用叶片泵和叶片式马达的叶片安装方向通常为( )。
【单选题】While sales by sample, if there is no other stipulations on the goods in the contract ,then the goods ______.
A.
may bd roughly the same as the sample
B.
may be the samle as the sample
C.
may have reasonalble tolerance
D.
may have reasonable difference on specification
【单选题】While sales by sample, if there is no other stipulations on the goods in the contract, then the goods _________.
A.
may be roughly the same as the sample
B.
must be the same as the sample
C.
may have reasonable tolerance
D.
may have reasonable differences on specification
【简答题】故障切除时间包括( )动作时间和( )动作时间。