How can a bicycles kinetic energy change when it slows down?

If 1 lb of fat is stored by the body for each 14.6×103kj of excess nutritional energy consumed, how long will it take this person to gain 1 lb?

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.

If angle "a" is 25°, angle "b" is: a) equal to angle c b) less than angle c c) greater than angle c