We have µ= g*µ_N*I/h_bar, which can be simplified to g=µ/µ_N*I.
1.a) we have µ=-0.5940, µ_N= 0.54502 nm/T and I =1/2. The g-factor of the ground state level of 111Cd is g = -1.1665.
For 111Cd at 245keV, µ=-0.766 , µ_N= 0.54502 nm/T and I = 5/2. So g=-1.214.
1.b) g=µ/µ_B*S. where magnetic moment = 1 mµB and S=1/2. So g = 2.