A daring ranch hand sitting on a tree limb vi = m/s wishes to drop vertically onto a horse galloping under the tree. The constant speed of the horse is m/s, and the distance from the limb to the level of the saddle is m. (a) What must be the horizontal distance between the saddle and limb when the ranch hand makes his move? (b) For what time interval is he in the air where a = m/s^2 and yf = m ?