4. Imagine you are driving a car on a highway, and your distances (in meters) from a certain point is given by the function s(t) = 30t - 2t, where t is the time in seconds since you passed that point. (a) Determine the time at which you pass the point for the second time. (b) Calculate your average speed over the first 10 seconds after you pass the point for the first time. (c) Find the limit of your average speed as t approaches 0. Interpret the meaning of this limit in the context of the problem. Hint: Average speed over an interval [a, b] is given by s(b)-s(a) b-a