What are the arbitrage profits i can make today?

Today's spot price of gold is $1600 per ounce. The continuously compounded interest rate is 5 percent per year. The quoted six-month forward price for gold is $1650. Suppose that trades now require a transactions cost of $3 per ounce whenever spot gold is traded, a $2 per ounce one-time fee for trading forward contracts, but no charges for trading bonds. If you have to pay transactions costs, the arbitrage profit that you can make today by trading one forward contract and other securities is