Ryan is self$-$employed. This year Ryan used his personal auto for several long business trips. Ryan paid $$1,740$ for gasoline on these trips. His depreciation on the car if he was using it fully for business purposes would be $$4,800.$ During the year, he drove his car a total of $15,000$ miles $($a combination of business and personal travel$).$

Note: Do not round intermediate calculations. Round your final answers to the nearest whole dollar amount.

a$.$ Ryan can provide written documentation of the business purpose for trips totaling $6,000$ miles. What business expense amount can Ryan deduct $($if any$)$ for these trips?