Can anyone please help me answer this question?
QUESTION: A web designer creates an animation in which a dot on a computer screen has a position of r = [ 4.0 cm + (2.5 cm/s^2)t^2] i + ( 5.0 cm/s ) t j.
1. Find the magnitude of the dot's average velocity between t = 0 s and t = 2 s.
2. Find the magnitude of the instantaneous velocity at t = 2.0 s.