Select all the relations which are not functions. {(x,y) is the color of a traffic light and y is the lawful response of an approaching motorist to that light} {(x,y) | is a randomly selected person and y is that person's birthday} {(x,y) a is the suggested retail price of particular car and y is price paid by a random car buyer for that car} {(x, y) {(x,y) is the date and y is the value of a stock at the close of the stock market that day} is an amount of alcohol consumed and y is the blood alchohol concentration for a person consuming that amount of alcohol}