sd(92) just before willy is forced to confront memory of error in boston, about to be given news of biff's math failure, the single trumpet is a means to signal the attention toward the events unfolding- not soft like a flute, more telling of the urban world where failure is final, green light links to biff's desire to work in nature, showcasing this as a turning point for biff as it's what inevitably causes him to work on farms instead of attending university (accepting the family's natural adoration for nature)