A.动能发生变化速度一定变化
B.速度发生变化,动能一定发生变化
C.动能是矢量
D.动能是标量,速度是矢量
答案:D
We're just trying to reach a point _______ both sides will sit down together and talk.[ ]
A. where
B. that
C. when
D. which
渗透泵型控释制剂的促渗聚合物
A.醋酸纤维素.B.乙醇C.聚氧化乙烯(PEO)D.氯化钠E.1.5%CMC-Na溶液