Consider a projectile fired with an initial velocity perpendicular to an incline sloping downward at an angle a with respect to the horizontal. When it eventually lands on the incline, let its velocity make an angle 0 with respect to the horizontal. Obtain the |(a) angle 0, (b) the value of a that yields the minimum value of 0, and (c) the corresponding value of this minimum 0. (d) If a rock is thrown at the top of the same incline, what angle 0 from the horizontal should rock be thrown so that it has the greatest range?