血药浓度降至最低有效浓度直至完全从体内消除的时间为( )。
A.潜伏期B.持续期C.失效期D.残留期E.消除半衰期
参考答案:D
解析:[知识点] 药物的量效关系
________Yan yanhong, a kindergarten teacher in Zhejiang Province ________ the boy by holding up him by his ears, his feet about 10 cm off the ground, she ________ free to live her own life now.
A.If; didn’t abuse; would be
B.Had; not abused; would have been
C.If; shouldn’t abuse; should have been
D.Had; not abused; would be
一家研究机构从IT从业者中随机抽取500人作为样本进行调查,其中60%的人回答他们的月收入在5000元以上,50%的回答他们的消费支付方式是使用信用卡。这里的“月收入”是()
A、分类变量
B、顺序变量
C、数值型变量
D、离散变量