N3﹣称为叠氮离子,1个N3﹣中共含有 ____个电子,与N3﹣离子有相同电子数和原子数的分子有(写出2种) ____
把下面的假分数化成整数或带分数.
289 =____
5213 =____
They were smoking the teacher appeared in front of them.