2-Benzyl-1,4,5,6-tetrahydropyrimidines 1 (as ene-1,1-diamine N,C-tautomers) in diglyme reacted with ethyl benzoylacetate at 160 °C in an oil bath to give 1,2,3,4-tetrahydropyrido[ 1,2-a]pyrimidin-6-ones 3 and with dimethyl acetylenedicarboxylate in methanol at room temperature,...
已知一组数据1,2,2,5,5,6的第60百分位数为,随机变量X的分布列为 2 m 14 0.3 0.6 0.1 ( ) A. 5 B. 6 C. 9.8 D. 10.8 相关知识点: 试题来源: 解析 D 【分析】 先求的值,再求的期望与方差. 【详解】 ∵,∴, ∴, ∴ 故选:D