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This question: 4 Previous question point(s) possible An object moves along the y-axis (marked in feet) so that its position at time x (in seconds) is given by the function f(x) = x - 15x2+ 72x. a. Find the instantaneous velocity function v = f' (x). b. Find the velocity when x = 1. c. Find the time(s) when v = 0. a. V= b. The velocity of the object at x = 1 is |fu/s. (Simplify your answer.) c. The velocity is zero at x = seconds. ents (Simplify your answer. Use a comma to separate answers as needed.) lan ook