In the expression 2(10x) + 15y, x represents the number of hours nina works in a week at a clothing store and y represents the number of hours she works in a week as a babysitter. the expression shows how much money nina has earned this month. which statement is true?

nina has worked a total of x – y hours so far this month.
nina works 15 hours a week at the clothing store.
nina makes 20x dollars at the clothing store each week.
nina makes $10 per hour babysitting each week.