Lifting off at sunrise,the hot air balloon goes wherever the

Lifting off at sunrise,the hot air balloon goes wherever the The hot air make the balloon stay up.中文是什么 The hot air makes the balloon stay up(划线提问) The hot air 划线 The rate of change of the altitude of a hot-air balloon is g 一个物理题.帮帮,A hot air balloon decends toward the ground with a hot-air balloon的意思 Hot off the heels rise like a hot-air balloon是什么意思? fairy,reporter,hot air balloon是什么意思? first hot air balloon啥意思? the hot air moves up__it gets cold it cooled down the hot air