Samantha has found a great deal on an acoustic guitar, but she doesn’t have enough money saved up to buy it. She convinces her parents to loan her $150 so that she can buy it. At the end of each week that Samantha has not paid back the loan, she has to add $3 to how much she owes her parents. If she is able to save up enough money to pay her parents back $20 each week, which of the following expressions correctly represents how much she will still owe her parents after t weeks?