On August 1, 2020, Ayayai Corporation purchased a new machine for its assembly process at a cost of $118,800. The company estimated that the machine would have a trade-in value of $14,400 at the end of its useful life. Its useful life was estimated to be six years and its working hours were estimated to be 15,000 hours. Ayayai's year end is December 31.

2020. (Do not round intermediate calculations. Round final answer to O decimal places, eg. 5,275.)

a. Straight-line depreciation for 2020

b. Activity method for 2020 assuming it was 700 hrs

c. sum of the years digits for 2021

d. double declining for 2021