()又称为便利抽样、偶遇抽样,是根据调查者的方便与否来选取样本的方法。
A.系统抽样
B.整群抽样
C.分层抽样
D.任意抽样
参考答案:D
治疗急性胰腺炎,禁用()
A.抗胆碱能药物
B.给钙
C.补充血容量
D.吗啡止痛
E.胃肠减压
Many lifestyle patterns do such______great harm to health that they actually speed up ______weakening of the human body.
A.a;/ B./;theC.a;the D./;/