I In Exercises 14-21, find the exact global maximum and minimum values of the function. The domain is all real numbers unless otherwise specified. I In Exercises 2227, find the best possible bounds for the function. 22.223 4&?2 +4;r:,for0 g :8 g 4 34. A grapefruit is tossed straight up with an initial velocity of50 ft/sec. The grapefruit is 5 feet above the ground when it is released. Its height, in feet, at time t seconds is given by y :16t2 + 50 + 5. How high does it go before returning to the ground