show work , please explain what nominal means here , and try to show steps in details please, I'm really struggling with these .

To buy a condo, Sally takes out a 15-year mortgage of 110000 dollars at a nominal interest rate of 6.9 percent convertible monthly, with the first payment due in one month. If she will make monthly payments that increase by 0.03 percent per month, how much is her first payment? Answer = dollars