Tom placed the bank notes ，_________the change and receipts ，back in the drawer ．
D
暂无解析
The poor countries are extremely _______to international economic fluctuations
设数列 {an} 的前 n 项和为 Sn，则 {an} 等差。
(1) S n4=n 2+2n, n=1,2,3
(2) S n4=n 2+ 2n +1,n=1,2,3
Tomplacedthebanknotes，_________thechangeandreceipts，backinthedrawer．
Idon’tthinkyou'llchangehismind；oncehe’sdecidedonsosomethinghetendsto_____it.
Successfullearningisnota(n)________activitybutconsistsoffourdistinctstagesinaspecificorder