A jet airplane in level flight has a mass of 8.66 × 104kg and the two wings have an estimated total area of 90.0m2. (a) What is the pressure difference among the lower and upper surfaces of the wings? (b) If the speed of air under the wings is 225m/s, what is the speed of the air over the wings? Suppose air has a density of 1.29kg/m3. (c) Describe why all aircraft have a “ceiling,” a maximum operational altitude.