Show all calculations please! Thank you!

Suppose a person is going up in a hot air balloon. The surrounding air temperature in degrees Fahrenheit decreases with height according to the formula T(h) =71 e -0.000065h where h is the height in feet. How fast is the temperature decreasing when the person is at a height of 800 ft and rising at a speed of 780 ft/hr? The temperature is decreasing at degrees hour (Round to the nearest tenth as needed.)