1. What are the different functions of the following graphs? When do we use them? Bar graph 口天然气 旅馆 五月1.What are the different functions of the following graphs? When do we use them? 0 5 1 0 1 5 2 0 2 5 3 0 3 5 一月 二月 三月 四月 五月 六月 食物 天然气 旅馆 Bar graph