Answer: The momentum of the fullback is 350 kg.m/s
Step-by-step explanation:
Momentum is defined as the force that keeps the object moving.
It is also defined as the product of mass and velocity of an object.
Mathematically,

where,
p = momentum of the fullback = ?
m = mass of the fullback = 100 kg
v = velocity of the fullback = 3.5 m/s
Putting values in above equation, we get:

Hence, the momentum of the fullback is 350 kg.m/s