( ( ( ( About ( the size ) ) ( of ( the wavelength ) ) ) ( of ( visible light ) ) ) . )
(ROOT (NP (NP (RB About) (DT the) (NN size)) (PP (IN of) (NP (DT the) (NN wavelength))) (PP (IN of) (NP (JJ visible) (NN light))) (. .)))
About the size of the wavelength of visible light.
(ROOT (S (NP (JJ Exact) (NN wavelength)) (VP (VBZ determines) (NP (NP (DT the) (NN color)) (PP (IN of) (NP (JJ visible) (NN light))))) (. .)))