Please help with the following:

To go on a summer trip, Reuben borrows $800. He makes no payments until the end of6 years, when he pays off the entire loan. The lender charges simple interest at an annual rate of 4%. Answer the following questions. If necessary, refer to the list of nancial formulas. (a) How much total interest will Reuben have to pay? X S r? $] (b) What will the total repayment amount be (including interest)? $[l