I want someone to check my homework to see if I'm doing is correct

(4) On January 1, 2012 a machine with a useful life of four years and a residual value of $8,000 was purchased for $40,000. What is the depreciation expense for year 2 (2013) under straight-line depreciation? What is the net book value of the machine at the end of December 31, 2013 (year 2)?

my answer is

40,000 - 8,000 = 32,000

32,000 / 4 = 8,000 deprc.exp.

40,000 - 16,000= 24,000 is Net Book Value

Your answer is correct.