The order of the ligand in the spectrochemical series is H2O < NH3 < NO2-.
Hence the wavelength of the light observed will be in the order :
[Ni(H2O)6]2+ < [Ni(NH3)6]2+ < [Ni(NO2)6]4-
Thus, the wavelength of light absorbed (E = \(\frac{hc}{\lambda}\) ) will be in the opposite order :
[Ni(H2O)6]2+ > [Ni(NH3)6]2+ > [Ni(NO2)6]4-