Answer:

Explanation:
From the question we are told that
Nucleus diameter 
a 12C nucleus
Required kinetic energy 
Generally initial speed of proton must be determined,applying the law of conservation of energy we have

where
=initial kinetic energy
=final kinetic energy
=initial electric potential
=final electric potential
mathematically

where
=distance b/w charges
=nucleus charge 
=constant
=proton charge
Generally kinetic energy is know as

Therefore
Generally equation for radius is 
Mathematically solving for radius of nucleus


Generally we can easily solving mathematically substitute into v_1









Therefore the proton must be fired out with a speed of 
The gas that gives Neptune and Uranus its amazing blue color is methane
The formula for momentum is p=mv where p is the momentum (kgms-1), m is the mass (kg) and v is the velocity (ms-1). So, to work out the momentum, we just multiply these numbers together and work out which is the largest.
1) 12kgms-1
2) 10kgms-1
3) 27kgms-1
4) 16kgms-1
Therefore the object with the greatest momentum is 3 - a 9kg mass moving at 3m/s