【单选题】把10克糖溶解在100克水里,糖和水的比是( )
【简答题】A.He was annoyed. B.He was pleased. C.He felt it could be replaced. D.He did not care.
【简答题】( 2 +1 ) 10 ( 2 -1 ) 11 =______.
【单选题】把10克糖放入100克水中,糖与糖水的重量比是( )
【简答题】A.He was quite happy. B.He felt upset. C.He didn't care. D.He seemed pleased.
【简答题】铰链四杆机构在 两位置处出现最小传动角。A. 曲柄与机架共线的
【单选题】已知活动铰链中心位置,设计铰链四杆机构的实质是确定()的位置