【多选题】有关标准误的描述正确的是:?
C.
标准误大小与原总体的标准差σ成正比,与样本含量n的平方根成反比
D.
只有增大抽样样本含量才能降低样本平均数的抽样误差
【判断题】我国旅游业加快改革步伐始于1985年国务院批准的国家旅游局《关于当前旅游体制改革几个问题的报告》之后。
【单选题】They letting him go and would like him to stay on after his present contract expires. prefix="o" ns="urn:schemas-microsoft-com:office:office" ?xml:namespace>
D.
had no intention at prefix="o" ns="urn:schemas-microsoft-com:office:office" ?xml:namespace>
【单选题】They would not allow him _____ across the enemy line. prefix="o" ns="urn:schemas-microsoft-com:office:office" ?xml:namespace>
【简答题】Twenty years ago, I was told a story of Little Brother at a party which has delighted and inspired me ever since. Little Brother, who was an ambitious painter and trying to be an artist, went to Franc...
【单选题】下列删除文件的操作,文件删除后无法还原的是()。
【单选题】关于肿瘤分级的描述不正确的是
C.
肿瘤的分级是制订治疗方案和估计预后的重要指标之一
E.
肿瘤分级的主要依据:肿瘤的分化程度、异型性和核分裂象的数目