18. Calculate the altitude of the eagle

An eagle is flying at a speed of 130 $km/h$. If the angle of elevation of an eagle from a point on the ground is 45$^{\circ}$. After 13 seconds, the angle of elevation changes to 30$^{\circ}$, then the altitude of the eagle from the ground is -0.2910.7091.7092.709 $km$. (Use $\frac{1}{\sqrt{3}} = 0.577$)