A:whose; which
B:of which; who
C:of whom; which
D:who; that
下列各组词语中错别字最多的一组是( )
已知(a2+1)n(a≠0)展开式中各项系数之和等于(165x2+1x)5展开式的常数项.
(1)求n值;
(2)若(a2+1)n展开式的系数最大的项等于54,求a值.