The atmospheric pressure at sea level is 14.7 pounds per square inch. Suppose that, at any elevation, an increase of 1 mile results in a decrease of 20% of the atmospheric pressure at that elevation.
(a) Find the difference equation for yn, the atmospheric pressure at elevation n miles.
(b) Solve the difference equation from part (a).
(c) Use the solution from part (b) to calculate the atmospheric pressure at 12 miles above sea level?