(4.4 - 4.5) This question: 1 point(s) possible A keyboarder's speed over a 4-min interval is given by the following function, where W(t) is the speed, in words per minute, at time t. O 60 W(t) = - 6t + 12t + 48 40- a) Find the speed at the beginning of the interval. b) Find the maximum speed and when it occurs. 20 c) Find the average speed over the 4-min interval. a) The speed at the beginning of the interval is | |words per minute. (Simplify your answer.) b) The maximum speed is words per minute and it occurs at t= min. (Simplify your answers. Type integers or decimals.) c) The average speed over the 4-min interval is words per minute. (Simplify your answer.) Time Remaining: 00:45:34 Next