Suppose an object moves along the y-axis so that its location is y = f(x) = x 2 + x at time x (y is in meters and x is in seconds). find the instantaneous velocity at x = 4 seconds

Your friend uses c=50p to find the total cost, c, for the people, p, entering a local amusement park is the cost of admission proportional to the amount of people entering the amusement park? explain.