Bus Acquired Cost Salvage Value Useful Life in Years

Question

1 1/1/13 $98,100 8,000 5 (straight-line)
2 1/1/13 129,000 11,900 5 (decline balance)
3 1/1/14 79,780 8,200 4 (units-of-activity)

For the declining-balance method, the company uses the double-declining rate. For the units-of-activity method, total miles are expected to be 119,300. Actual miles of use in the first 3 years were: 2014, 24,400; 2015, 31,900; and 2016, 29,700.
Depreciation Expense: .60 per mile

Compute the amount of accumulated depreciation on each bus at December 31, 2015.

Please help thank you!