Answer:
Momentum is Mass x Velocity.
Its pretty obvious that the 80kg student Moving at 4ms-¹ has more momentum.
80x4 = 320kgms-1
0.001x250= 0.25kgms-¹
The Second student also Has More Inertia. Inertia is the resistance to motion offered by a Body. An Object with greater mass has more tendency to resist Motion .
So
The 80Kg student wins all.