Each of the two wings of an aeroplane has area `30m^(2)`. The speed of the air on the upper and lower surfaces of theon the wing of aeroplane are `90 ms^(-1)` and `70 ms^(-1)` respectively. If the plane is in level flight at constant speed, find the uplift and the mass of the aeroplane. Given density of air `=1.29 kg m^(-3)`.