Ryan is self-employed. This year Ryan used his personal auto for several long business trips. Ryan paid $2,120 for gasoline on these trips. His depreciation on the car if he was using it fully for business purposes would be $5,700. During the year, he drove his car a total of 20,100 miles (a combination of business and personal travel).

a. Ryan can provide written documentation of the business purpose for trips totaling 6,030 miles. What business expense amount can Ryan deduct (if any) for these trips?

b. Ryan estimates that he drove approximately 1,785 miles on business trips, but he can only provide written documentation of the business purpose for trips totaling 1,100 miles. What business expense amount can Ryan deduct (if any) for these trips?