已知函数f(x)=﹣x2+2x+3在[0,3]上的最小值为____
要使四位数825□能被3整除,□里最小应填( )
如图是反射与反射弧的图解,正确的是( )
The idea of “sunshine sports”makes it possible for kids to choose and do _______ about sports as long as one hour every day.