句子排序。
(____)A.Of course.Here you are.
(____)B.How much is it?
(____)C.Yes.Can I try on this skirt?
(____)D.It's $100.
(____)E.Can I help you?
(____)F.I will take it.
如图,在平行四边形ABCD中,对角线AC,BD相交于点 O,若BD,AC的和为18 cm, CD∶DA=2∶3 ,△AOB的周长为13 cm,那么BC的长是( )
下列说法错误的是( )