1. 设集合,,则∁R等于 A. B. C. D.
由于电泳,硫化砷的胶粒移向阳极,由此可推断硫化砷胶粒( ) A.带负电荷 B.带正电荷 C.
I would love _____ to the party last night but I had to work extra hours to finish a report. A. to go B. having gone C. going
文物考古和鉴定往往需要运用相关的知识进行分析和辨别。而其中有些赝品往往只需用肉眼就能轻易作出判断,请仔细观察和辨别下列铜币的拓片,其
Dear Linda,I'm glad to hear from you and I would like to be your pen friend. In your letter, you said you wanted to know something about my school life(生活). I walk to school at 7:30 every morning
下图表示人体消化吸收过程,①——⑤表示消化液(⑤为肠液)。纵向箭头表示消化液对相应物质的消化作用,a、b、c分别表示淀粉、蛋白质和脂肪的
某公司市场营销部的个人月收入与其每月的销售量成一次函数关系,其图象如图所示,由图中给出的信息可知,营销人员没有销售时的收入是( )