Answer: The difference between Javier's and Kyle's pay.
Explanation:
Given: Javier and Kyle work installing windows and can earn extra money by installing doors.
Javier earned $56 more than Kyle because of door installations.
⇒ The difference between Javier's and Kyle's pay= $56
Therefore, in the expression which represents Javier's pay for the week: 14w + 56 , the constant term represents the difference between Javier's and Kyle's pay.