A:short
B:long
南北朝傅翕曾写下这样一首诗:“空手把锄头,步行骑水牛.人在桥上走,桥流水不流.”其中“桥流水不流”一句应理解成其选择的参考系是( )
已知锐角α且5α的终边上有一点Psin-50°,cos130°,则α的值为( )
Mary's dress is very similar________mine but they differ________quality.
求函数y=cos2x+2sinx﹣2值域.