题目

Last year, I was on a plane with my friend, waiting for it to take off. The pilot’s voice was heard throughout the plane: “Sorry for the delay, ladies and gentlemen. Our engines don’t work. We are going to jump-start them. Once we get them going, we’ll get up in the air and see what happens.” That was all he said. “See what happens?” Shouldn’t we have had a better plan than that? At that point. I could only laugh nervously. One woman started crying, “Oh no! We are going to crash!’’ There were sighs of hopelessness and anxiety, and we hadn’t even taken off yet. T 在三亚一中80周年校庆开幕式上，五颜六色的汽球冉冉升空．升空的汽球中填充的气体是________(填写中文名称或化学式均可)．请你写出制取该气体的三个化学方程式： ①__________________ ②__________________ ③__________________