A:other tha
B:or rather
C:rather tha
D:more tha
To________ telling lies, he asked his friend to help him cheat his parents.( )
下列不是由细胞构成的生物是( )
如下图一物体以某一速度冲上表面粗糙的固定斜面, 请画出物体在上滑过程中所受到的重力G和摩擦力f 的示意图。