Answer:

Explanation:
The momentum of the neutron before and after the decay is the same since there's no external force.

#The neutron is initially at rest, so after the decay:

#After decay, the proton has +ve direction with a velocity
while the electron moves in a negative direction with a velocity 
Therefore:

Let the energy released during the decay be Q:

Hence,Kp/Ktot is 5.444x10^(-4)
No work is being performed on the object unless the object is moving, as work done = force x distance
Potential energy is first transformed into kinetic energy as she pedals, then gravitational as she coasts down the hill.