In the expression 2(10x) 15y, x represents the number of hours Nina works in a week at her first job and y represents the number of hours she works in a week at her second job. The expression shows how much money Nina has earned this week. Which statement is true? Nina has worked a total of x – y hours so far this week. Nina works 15 hours a week at her first job. Nina makes 20x dollars at her first job each week. Nina makes $10 per hour at her second job each week.