Thousands of people were attracted to a 2-meter-wide lane in Tongcheng,Anhui province this spring festival. Although_61_was impossible to count the exact number,at least 5,000 people visited it eac
One day, Wilson was walking quietly along the road when someone hit him hard on the back of his neck. He looked behind him, and saw a young man whom he had never seen before. “How dare
互为同系物的是( )
分子中含有一个醇羟基和一个苯环，根据同系物的定义，可以判断只有C项中的物质符合同系物的定义；A、B项中的物质含有酚羟基，不是同类物质；D项中的物质分子中含有2个羟基，且一个为醇羟基，一个为酚羟基。