1a) I have as a result -25*10^-9 kg*nm/C, however I do not know if my calculation is completely right, since I am not sure about the units, considering me the g-factor is dimensionless.
What I did is writting g = hbar/mu_n * mu/I, then I wrote mu_n as e hbar/2m_p and filled in all numbers.
For the 245KeV level I found: g_ground/5 = -5*10^-9 kg*nm/C
1b) We know that g_e = mu*hbar/(mu_B*S) = 2hbar
1c) -4*10^-8 C/kg, again I am worried about the units.