Solve it correctly please. I will rate accordingly with multiple votes. This is my last attempt. Answer only if 100% correct.

7. [-/1 Points] DETAILS SERPSE10 2.7.OP.019. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER A particle moves along the x axis. Its position is given by the equation x = 2.1 + 2.8t - 3.6t with 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 Need Help? Read It Watch It