“Excuse me, could you tell me ____?”“OK. It's on the Main Street.”
A:where was the supermarket
B:where is the supermarket
C:where the supermarket is
当光从空气射入水中,入射角为40°,则折射角可能为( )
它们的茎显得坚韧而苍老,叶因枯萎而失却光泽,只有根竟似强固的筋条,仿佛柔中带刚的藤wàn____,深埋在石缝狭ài____的间隙里,默默成为攀登者可靠的抓绳。生命就是这样被环境限制着,又被环境改变着,适者生存的规律尽管无情,但生命原本就是拼搏。
已知链式炔碳C300经过适当处理可得含多个(不含)的链状化合物C300H298,则含的个数为( )