In a scattering experiment, an alpha particle A is projected with the velocity u0 = ?(600 m/s)i

Question:

In a scattering experiment, an alpha particle A is projected with the velocity u0 = ?(600 m/s)i + (750 m/s)j ? (800m/s)k into a stream of oxygen nuclei with a common velocity v0 = (600 m/s)j . After colliding successively with nuclei B and C, particle A is observed to move along the path defined by the points A1 (280, 240,120) and A2(360, 320, 160), while nuclei B and C are observed to move along paths defined, respectively, by B1 (147, 220,130) and B2 (114, 290,120), and by C1 (240, 232, 90) and C2 (240, 280, 75). All paths are along straight lines and all coordinates are expressed in millimeters. Knowing that the mass of an oxygen nucleus is four times that of an alpha particle, determine the speed of each of the three particles after the collisions.