1a) g = µ*h_bar / µ_N*I, with µ = -0.59403µ_N, I = 1/2 h_bar to give g = -0.59403 / (1/2) = -1.18806 for the ground state. For the 245 keV state, µ = -0.766µ_N and I = 5/3 h_bar to give g = -0.766 / (5/2) = -0.3064.
1b) µ = g*µ_B*I, with µ = µ_B, I = 1/2 to give g = µ / µ_B*I = 1 / (1/2) = 2.
1c) µ = g*µ_N*I with g = -3.826 and I = 1/ to give µ = -3.826*(1/2)*µ_N = -1.913µ_N.