Consider a system consisting of three particles: ......?

Consider a system consisting of three particles: m1 = 2 kg, vector v1 = < 9, -8, 15 > m/s m2 = 5 kg, vector v2 = < -15, 3, -5 > m/s m3 = 3 kg, vector v3 = < -28, 39, 23 > m/s

a) What is the total momentum of this system?
b) What is the velocity of the center of mass of this system?
c) What is the total kinetic energy of this system? Ktot = J
d) What is the translational kinetic energy of this system?
e) What is the kinetic energy of this system relative to the center of mass?