Three complex ions of cobalt(III), [Co(CN) 6 ] 3 , [Co(NH 3 ) 6 ] 3+ ,

Question:

Three complex ions of cobalt(III), [Co(CN)₆]³¯, [Co(NH₃)₆]³⁺, and [CoF₆]³¯, absorb light at wavelengths of (in no particular order) 290 nm, 440 nm, and 770 nm. Match each complex ion to the appropriate wavelength absorbed. What color would you expect each solution to be?