At a certain instant a particle (mass=0.5 kg) is moving in the +x direction with velocity 14 m/s. During the next 0.15 seconds a constant force acts on the particle, with Fx= ?8 N and Fy= Fz = 0 N. What is the magnitude of the momentum of the particle (in kg*m/s) at the end of this 0.15 second interval?