public void SelectProductWithExcessCreditGetAppropriateChange()
        {
            VendingMachine.InsertCoin("Quarter");
            VendingMachine.InsertCoin("Quarter");
            VendingMachine.InsertCoin("Nickle");
            VendingMachine.InsertCoin("Dime");
            VendingMachine.InsertCoin("Dime");
            VendingMachine.InsertCoin("Quarter");
            VendingMachine.ButtonPressed(2);  //Cost of .5  total is $1.00

            var change = VendingMachine.GetValueOfCoinReturn();

            Assert.AreEqual(change, 0.5);
        }