有人秀着“鸟叔”的马步自得其乐，有人把玩着“苹果”追逐时尚，有人追捧某歌手为“星之大侠”，有人为“三国杀”寝食皆忘……面对这种现状，正确选择应是
①善于模仿，顺势而为               ②明辨是非，择善而行
③理性思考，绝不盲从               ④兴趣多元，跟风弄潮

（1）ClO₂是一种新型的自来水消毒剂，工业上用Cl₂与NaClO₂制取ClO₂，发生反应的化学方程式为：□Cl₂+2NaClO₂→2NaCl+□ClO₂，请在□中填入配平后的系数____ 　、____ ．

（2）常见的化石燃料有煤、石油和天然气等，天然气主要成分是____ ．

    It is the world's most well-known and popular song. It has been sung hundreds of millions of times each year. It has been heard in outer space, at baseball stadiums, in movies and in domiciles(住处)from the White House to the most remote(遥远的) backwoods shack(窝棚) in Misissippi. It has been wired into millions of music boxes, greeting cards, watches, toys, games and other tune-playing products. And it is the only song in the English language to make people of all ages smile and sing along. The song, of course, is Happy Birthday to You".

    This amazing song began its life in 1893. Written by two sisters from Kentucky, Mildred and Patty Hill, it was originally (起初) named “Good Morning to All”, and intended as a classroom greeting from teachers to students:

    Good morning to you

    Good morning to you

    Good morning, dear children

    Good morning to all.

    To this day, no one knows for sure who wrote the new words to Hill's melody(旋律),or exactly when it happened. “Happy Birthday to You” first appeared in a songbook in1924.The words were presented as the second stanza(节) to "Good morning to You".

臭氧（O₃）可用于杀菌消毒，下列有关臭氧的说法正确的是（　　）