A Honda Civic travels in a straight line along a road. Its distance x from a stop sign is given as a function of time t by the equation

x(t) = 1.5t² - 0.05t³

and its velocity is given by

v(t) = 3t - 0.15t²

1. Calculate the average velocity of the car for time interval t = 2 s to t = 4 s.
2. Calculate the instantaneous velocity at t = 5 s.