如图，矩形ABCD的边AB在x轴上，顶点C，D在函数y=x+ $\frac{1}{x}\left(x>0\right)$ 的图象上．记AB=m，BC=n，则 $\frac{m}{n^2}$ 的最大值为____．

8和x的比等于4和5的比.

____∶____ = ____∶____

x=____

   Tom and Gina usually go to school by car .They drive(驾车) pasta cinema a supermarket a post office. The post office is next to the supermarket on Center Street .Mary and Ann usually go to school by bus. They go down Sixth Avenue, past a bank and a library. The bank is across from the library. Jenny usually goes to work by bike,he rides(骑车) past a hotel and three streets．