please explain in detail. If possible, please have it in excel. thank you

29.14. What is the value of a European swap option that gives the holder the right to enter into a 3-year annual-pay swap in 4 years where a fixed rate of 5% is paid and floating is received? The swap principal is $10 million. Assume that the volatility of the swap rate is 20%, all swap rates are are 5%, and all OIS rates are 4.7%. Compare your answer with that given by DerivaGem. 29.14. What is the value of a European swap option that gives the holder the right to enter into a 3-year annual-pay swap in 4 years where a fixed rate of 5% is paid and floating is received? The swap principal is $10 million. Assume that the volatility of the swap rate is 20%, all swap rates are are 5%, and all OIS rates are 4.7%. Compare your answer with that given by DerivaGem