Jace is a songwriter who collects royalties on his songs whenever they are played in a commercial or a movie. jace will earn $50 every time one of his songs is played in a commercial and he will earn $140 every time one of his songs is played in a movie. jace's songs were played on 6 more commercials than movies, and his total earnings on the royalties from all commercials and movies was $680. determine the number of commercials and the number of movies on which jace's songs were played.