A web page designer creates an animation in which a dot on a computer screen has a position of r = [4.0 cm + (2.5 cm/s2)t2]i + (5.0 cm/s)tj.
(a) Find the magnitude and direction of the dot's average velocity between f = 0 and I = 2.0 s.
(b) Find the magnitude and direction of the instantaneous velocity at t = 0, I = 1.0 s, and 1= 2.0 s.
(c) Sketch the dot's trajectory from I = 0 to I = 2.0 s, and show the velocities calculated in part (b)