Answer:
23.38 years
Explanation:
Speed of Allison = 0.83 c = v
Time passed according to Allison = Δt = 29.5 years
Time dilation

For Nora 52.88 years would have passed
So, their age difference would be 52.88-29.5 = 23.38 years
Since the position doesn't change over that time, it's zero
Force=(mass*velocity)-(mass*velocity)/time
force=0-(-15*1400)/0.30
force=70000N
1. the energy of the wave, 2.the type of medium. 3.the amplitude of the wave. 4.the type of wave