Thyunda said:
"What colour is this?"
There is no right answer, because I can't prove that my red is your red. Your red might actually be green, but you call it red and see everything red as green. So although you will say red, I can never know for sure that it's the same red I can see.
False.
It can be quantified as a color as according to the hexadecimal RGB spectrum. Whether or not you view colors the same (which seems unlikely, based on biology) is irrelevant, as the color is F2FF40, or B3270C, or 2394AE, etc.