What colors of ink do color ink-jet printers use to produce a full range of colors? Do the colors form by color addition or by color subtraction? In which of these cases will a ripe banana appear...

What colors of ink do color ink-jet printers use to produce a full range of colors? Do the colors form by color addition or by color subtraction? In which of these cases will a ripe banana appear black: when illuminated with red, yellow, green, or blue light?

Look at your red, sunburned feet when they are under water. Why don’t they look as red as when they are above water?