2. naca 2412 airfoil has a zero lift angle of -2.1 degree and a lift curve slope of 2  (if the alpha is expressed in radians). the pitching moment coefficient at the quarter chord is -0.036. compute the lift and pitching moment at quarter chord at a 4 degree angle of attack if the freestream velocity is 50 feet sec, and the chord is 2 feet. assume sea level conditions. (ans: 3.8 lb per foot of span, -0.428 ft. lb per foot of span)