--- Nick, _____ you ______ my book?
--- Sorry, I just came here.
A:have, seen
B:did, see
C:has, seen
D:do, see
如图,点C在线段AB上,AC=8cm,CB=6cm,点M,N分别是AC,BC的中点.求线段MN的长.
彩虹的美丽在于它的七色光彩,班级的美丽在于( )
比较大小: -58____ 12.