1- A particle moves along the x axis. Its position is given by the equation x = 2.1 + 2.9t ? 3.5t2with x in meters and t in seconds.
(a) Determine its position when it changes direction.
(m)
(b) Determine its velocity when it returns to the position it had at t = 0? (Indicate the direction of the velocity with the sign of your answer.)
(m/s)