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If a ball is thrown vertically upward with a velocity of 96 ft/s, then its height after t seconds is s = 96t - 16t2. (a) What is the maximum height reached by the ball? ft (b) What is the velocity of the ball when it is 128 ft above the ground on its way up? (Consider up to be the positive direction.) ft /s What is the velocity of the ball when it is 128 ft above the ground on its way down? ft/s Need Help? Read It Watch It