\([Fe(NH_3)_6]^{3+}, [Mn(CN)_6]^{4-}\) and \([Co(NH_3)_6]^{2+}\) are inner orbital complexes and are also paramagnetic in nature having magnetic moment of \(\sqrt 3 \,B.M.\)
$(a)$ $\left( NH _{4}\right)_{2}\left[ Ce \left( NO _{3}\right)_{6}\right]$
$(b)$ $Gd \left( NO _{3}\right)_{3}$ અને
$(c)$ $Eu \left( NO _{3}\right)_{3}$
$(I)\,K_3 [Fe(CN_6)]$ $(II)\, [Ni(CO)_4]^0$ $(III)\, [Cr(NH_3)_6]^{3+}$ $(IV)\, [Mn(CN)_6]^{4-}$
સાચો કોડ પસંદ કરો.
($R $ = alkyl group; $en$ = ethylenediamine)