Answer:
Phosphorus has a low melting point because the intramolecular forces holding it together is London Dispersion Forces.
Explanation:
London Dispersion Forces (LDF) are the weakest intramolecular forces. You don't need to break the covalent bonds, but rather the Van Der Waals' Forces. If LDF are the weakest forces, then the melting point is low.
The answer would be 6 e-. This is becuase you are turning a charge of -4 into a +2. In order to do this, you transfer 4 electrons for a neutral charge, and an additional 2 for a charge of +2.
This makes a total charge of +2, and the total transferred electrons 6 e-