Activity: 1. At t = 0s a particle moving in the x - y plane with constant acceleration has a velocity of vec v i =(3 hat i -2 hat j ) m / s , and is at the origin. Att = 3s the particle's velocity is vec v f =(9 hat i 7 hat j ) m / s . Find (a)the acceleration of the particle (b) Its coordinates at t = 3s