2008年9月,中国爆发三鹿婴幼儿奶粉受污染事件,导致食用了受污染奶粉的婴幼儿产生肾结石病症,其原因也是奶粉中含有三聚氰胺。三聚氰胺的化学式是C 3 N 6 H 6 。 (1)一个三聚氰胺分子中有_______个原子; (2)三聚氰胺中碳元素和氢元素的元素质量比是________; (3)三聚氰胺的相对分子质量是_________;
【单选题】The police ____ the murder everywhere when he suddenly appeared in the theatre. A.is searching for B.were searching for B.are searching for D.was searching for