没食子酸硫酸试剂

4-氨基安替比林-铁氰化钾

醋酐—浓硫酸

α-萘酚-浓硫酸

三氯化铁—铁氰化钾

无向图

树

循环链表

有向图

错误是弃真错误， 错误是取伪错误

错误是取伪错误， 错误是弃真错误

在样本容量既定的情况下， 和 不能同时增大或减少。

一般原则是，先控制 ，再使 尽量小。

正确

错误

正确

错误

正确

错误

survey of l, 423 a- dults by the University of Michigan's Institute for Social Research in 2001 found that people who had forgiven someone in their past also reported being in better health than those who hadn't. However, while 75 per cent said they were sure God had forgiven them for past mistakes, on-ly 52 per cent had been able to find it in their hearts to forgive others. Forgiveness, it seems, is still divine. 56.In Luskin 's opinion, people could enjoy better health if they________ . [A] hold past hurts back [

] avoid the wrongdoers [C] become less emotional [D] let off those who hurt them