A 6.2 kg bowling ball that weighs 60.76 N is accelerating at 1.8 m/s2. After 2 seconds, it reaches a speed of 3.6 m/s. What is its momentum at this point?
A. 22.3 kg-m/s
B. 16.9 kg-m/s
C. 11.2 kg-m/s
D. 1.7 kg-m/s

The ratio of lift to drag l/d for a wing or airfoil is an important aerodynamic parameter, indeed, it is a direct measure of the aerodynamic efficiency of the wing. if a wing is pitched through a range of angle of attack, l/d first increases, then goes through a maximum, and then decreases. consider an infinite wing with an naca 2412 airfoil. estimate the maximum value of l/d. assume that the reynolds number is 9x10^6.