Can you please help me figure out how the answer is B using a formula.

14. Over the last 5 years, the average nominal rate of return of 90 day Treasury bills was 1.02%, Saltine Co.'s average nominal stock return was 8.9%, large company stocks average nominal return was 15%, and the inflation rate averaged 2.7%. The real rate of Saltine's stock return is A) 6.8%. B) 6.0%. C) 5.1%. D) 4.3%. Answer: B