O'Brien Ltd.'s outstanding bonds have a $1,000 par value, and they mature in 25 years. Their nominal annual, not semiannual yield to maturity is 9.

O'Brien Ltd.'s outstanding bonds have a $1,000 par value, and they mature in 25 years. Their nominal annual, not semiannual yield to maturity is 9.25%, they pay interest semiannually, and they sell at a price of $875. What is the bond's nominal coupon interest rate?