Can someone please help me out.

Suppose a car is moving along straight road and distanct traveled t hours after starting from rest is given by f (t) = 2t^2+60t. Find the avg velocity of the car over the time intervals (0,2) and (1,2). Find the instanteaneous velocity at t = 1 and t = 2.

Can someone explain hte process of how to solve this? Using the method equations of

f (x+h) - f(x) / h

Thanks