An airforce plane is ascending vertically at the rate of $100 \mathrm{km}/h$. If the radius of the earth is $R \mathrm{km}$, how fast is the area of the earth is visible from the plane increasing at $3$ minutes after it starts?(Visible area $A=\frac{2\pi R^{2}h}{R+h}$, where $h$ is the height of the plane above the earth.)