The angle of elevation of the top of a hill from a point on the horizontal plane passing through the foot of the hill is found to be 45°. After…

The angle of elevation of the top of a hill from a point on the horizontal plane passing through the foot of the hill is found to be $\displaystyle 45$°. After walking a distance of $\displaystyle 80$ meters towards the top, up a slope inclined at an angle of $\displaystyle 30$° to the horizontal plane, the angle of elevation of the top of the hill becomes $\displaystyle 75^{\circ}$. Then the height of the hill (in meters) is \_\_\_\_.