Answer:
A)  If the paintball stops completely the magnitude of the change in the paintball’s momentum is  [tex]p=0.273kg*m/s[/tex]
B) If the paintball bounces off its target and afterward moves in the opposite direction with the same speed, the change in the paintball’s momentum is  [tex]p=0.546kg*m/s[/tex]
C) A paintball bouncing off your skin in the opposite direction with the same speed hurts more than a paintball exploding upon your skin because of the strength exerted is twice than if it explodes.
Explanation:
Hi
A) We use the formula of momentum [tex]p=mv[/tex], so we have [tex]p=0.0032kg*85.3m/s=0.273kg*m/s[/tex]
B) We use the same formula above, then due we have a change of direction at the same speed, therefore the change in the momentum is the double so
[tex]p=2*0.0032kg*85.3m/s=0.546kg*m/s[/tex].
C) The average strength of the force an object exerts during impact is determined by the amount the object’s momentum changes. therefore
[tex]F=\frac{\Delta p}{\Delta t}[/tex], as we don't have any data about the impact time but we know momentum is twice, time does no matter and strength is twice too.