问题 单项选择题

液化石油气、天然气、人工煤气的体积热值由高到低依次是()。

A、液化石油气、人工煤气、天然气

B、液化石油气、天然气、人工煤气

C、天然气、人工煤气、液化石油气

D、天然气、液化石油气、人工煤气

答案

参考答案:B

材料分析题

八年级的阳阳和明明是好朋友,一天,他俩互相述说自己的烦恼,阳阳说:“最近我的脸上长了一些红色的小疙瘩,遮不住也擦不掉,难看死了。”明明说:“我的喉咙突出来,象长了个东西似的,感觉很怪!”…… 你能帮助他们消除这些烦恼吗?并说一说你的办法。 

                                                                                                                                                               

                                                                                                                                                                

                                                                                                                                                               

                                                                                                                                                              

单项选择题