Like notaries, witnesses aren't generally required in order for a contract to be legally enforceable. However, each state may require special kinds of contracts (e.g., real estate deals, wills, and marriage agreements) to be witnessed by a third party in order to be binding.
McDonald's, apparently, use red and yellow because red=fast and yellow=hunger (hence fast food!). Remember also that meaning is what we create. It does not exist in the color itself and individual meanings may or may not exist in different cultures and individuals.
The favorable colors of Pisces Sign. Pisces - Yellow, white or cream color. Yellow is the safest color for a car but nobody likes to drive a lemon. Black color is selected by those cool guys. Red is a fast moving color. It means sexy, fast-moving, White cars look cool and smart but the owner should be able to clean it more often tha he cleans himself.