please solve with formula (without excel) Thanks

You are considering a bond that has a face value of $1,000 and matures in 15 years. During the first three years, no coupons will be paid. Over the subsequent seven years, coupons will be paid semi-annually at the end of each period, with a coupon rate of 2% per year compounded semi- annually. During the last five years, coupons will be paid semi-annually at the end of each period, with a coupon rate will be 4% per year compounded semi-annually. Calculate the current price of the bond, if the yield to maturity remains at 3% per year compounded semi-annually throughout the entire 15-year period. Show your calculation