Answer: Green
Although the human eye can distinguish up to a few hundred hues when those pure spectral colors are mixed together or diluted with white light the number of distinguishable chromaticities can be quite high. [ambiguous] In very low light levels vision is scotopic: light is detected by rod cells of the retina. Rods are maximally sensitive to wavelengths near 500 nm and play little if any role in color vision.
A spectrum (plural spectra or spectrums) is a condition that is not limited to a specific set of values but can vary without steps across a continuum.The word was first used scientifically in optics to describe the rainbow of colors in visible light after passing through a prism.As scientific understanding of light advanced it came to apply to the entire electromagnetic spectrum .
The human eye’s red-to-green and blue-to-yellow values of each one-wavelength visible color Human color sensation is defined by the sensitivity curves (shown here normalized) of the three kinds of cone cells: respectively the Short- Medium- and Long-wavelength types. Impossible colors are colors that do not appear in ordinary visual functioning.
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It is the light spectrum as the transmission medium …