Please review my calculation A , B and please help with C, also correct if there is wrong. Thank you

On January 1, 2021, Canseco Plumbing Fixtures purchased equipment for $44,000. Residual value at the end of an estimated four-year service life is expected to be $8,000. The company expects the equipment to operate for 20,000 hours. The equipment operated for 2,900 and 3,700 hours in 2021 and 2022, respectively.

Required: a. Calculate depreciation expense for 2021 and 2022 using straight-line method. b. Calculate depreciation expense for 2021 and 2022 using double-declining-balance method. c. Calculate depreciation expense for 2021 and 2022 using units-of-production using hours operated.

Calculate depreciation expense for 2021 and 2022 using straight-line method.

Straight-Line Depreciation
	Choose Numerator:	/	Choose Denominator:	=	Annual Depreciation Expense
Formula	Cost minus Residual	/	Estimated Useful Life (years)	=	Depreciation Expense
Amounts	$36,000	/	4	=	$9,000
	Depreciation Expense
2021	$6,750
2022	$9,000

Calculate depreciation expense for 2021 and 2022 using double-declining-balance method.

Double-Declining-Balance Method
	Choose Numerator:		Choose Denominator:		=	Depreciation Expense
Formula	Beginning Book Value		Straight-line Rate		=	Depreciation Expense
Amount for 2021	$44,000		50	%	=	$22,000
Amount for 2022	$22,000		50	%	=	$33,000

• Calculate depreciation expense for 2021 and 2022 using units-of-production using hours operated. (Round "Depreciation per machine hour" answers to 2 decimal places.)

  Select formula for Units of Production Depreciation:
  Calculate 2021 depreciation expense:
  Depreciation per machine hour
  Machine hours in 2021
  Depreciation in 2021
  Calculate 2022 depreciation expense:
  Depreciation per machine hour
  Machine hours in 2022
  Depreciation in 2022