【单选题】2019年9月30日,在庆祝中华人民共和国成立70周年招待会上,国家主席习近平指出:“我们要高举和平、发展、合作、共赢的旗帜,坚定不移走和平发展道路,坚持对外开放,同世界各国人民一道,推动构建人类命运共同体,让和平与发展的阳光普照全球”。这说明中国( )
【简答题】人类生存离不开能源。 (1)北京家用燃料的更新过程如下: ① 煤、液化石油气、管道煤气均属于_____(填“混合物”或“纯净物”)。 ② 天然气的主要成分是甲烷。甲烷在空气中充分燃烧的化学方程式是_____。 ③ 下列有关家用燃料更新的理由,正确的是_____(填字母序号)。 A.天然气属可再生能源 B.气体燃料比固体燃料利用率更高 C.减少煤燃烧过程中产生的污染物 D.气体燃料便于管道输送 (2...
【简答题】People often call the plastic bags “white pollution”. 小题1: , it becomes the worst invention for the human. It is reported that it takes 100–200 years to break down the plastic bags completely. However...
【判断题】零件表面粗糙度值越大,则零件的耐磨性越好。
【单选题】阅读理解1 One day a student went to see his teacher. He had been given an important position now and was coming to say goodbye. The teacher asked how he would get along with the high officials. The stude...
A.
He hadn't seen him for a long time
B.
He wanted his teacher to give him a job
C.
He would go to work among officials
D.
He would go to a place far away from his teacher
【判断题】蝶恋花·庭院深深深几许 》这首词的词牌名是“蝶恋花”。