If the question is "What measures of distance are used with (visible) light?" Light is normally measured either in Angstroms, which are ten-billionths of a meter, or, more commonly today, in nanometers, which are one-billionths of a meter. Red light is around 700-690 nanometers (some claim all the way to 760 nm) and the wavelengths get shorter as the colors get "cooler" (that's psychologically cooler; they are actually getting more energetic). Around 400-390 nm they slip into the ultraviolet and we can no longer see them.
690
85 percent of 690 = 586.5 85% of 690 = 85% * 690 = 85%/100% * 690 = 0.85 * 690 = 586.5
690
The product is 690
690
690
87-690 = -603
If you want to round 690 to hundreds the answer is 700 but with tens then 690 still
23 x 30 = 690
690
690