极限
参考答案:A
解析:[考点提示] 数列的极限. [解题分析] 令[*] 当n=2k(k∈N)时,[*] 当n=2k-1(k∈N)时,[*] 所以[*]
关于拔除牙的检查及拔牙创的处理,下列错误的是
A.检查拔除牙根是否完整
B.检查牙龈有无撕裂
C.过高牙槽间隔应待其自行吸收
D.刮除拔牙窝内残留物
E.牙槽窝压迫复位
No one can________how the election will turn out, as there are many unknown facts. [ ]
A. protect
B. prepare
C. prevent
D. predict