Please use EXCEL to solve it and show the equation, THANKS

The Spot price of gold is $250 per oz; 90- day custodian fee ( storage and Show your answers along with the formula and steps you used insurance , due at the beginning of the period ) = $4 per oz; The risk free for each question . interest rate is 6% p.a . The size of the futures contract is 100 0z . Use 30/360 day count convention and simple interest rate . A ) Ans :" A . Calculate the arbitrage - free price of a gold futures contract that expire in 90 days . ( 1 point ) B. Illustrate how an arbitrage profit can be made if the future contract is B ) Ans :" price at $ 260 per oz and calculate the arbitrage profit . ( 2 point ) C. Illustrate how an arbitrage profit can be made if the future contract is price at $250 per oz and calculate the arbitrage profit . ( 2 point ) C ) Ans :"