A radio plays 16 commercials in an hour. A commercial is either 30-seconds long or 60-seconds long. The total commercial time is 13 minutes. If x represents a 30-second commercial and y is a 60-second commercial, which equations would you enter into a graphing calculator to find how many of each type of commercial is played? Check all that apply. x + y = 13 x + y = 16 0.5x + y = 13 0.5x + y = 16 0.5x + y = 29