单项选择题在碳原子数相同时，裂化反应能力排列正确的是( )。 A、烯烃>环烷烃>芳烃>烷烃 B、烯烃>烷烃>芳烃>环烷烃 C、烯烃>环烷烃>烷烃>芳烃 D、烯烃>芳烃>环烷烃>烷烃
单项选择题The largest horizontal-axis turbines are as tall as ( ) buildings and have blades more than ( ) feet long.A.20-story 100B.2-story 200C.10-story 300D.5-story 100
