Starling Co. is considering disposing of a machine with a book value of $24,800 and estimated remaining life of five years. The old machine can be sold for $5,800. A new high-speed machine can be purchased at a cost of 66,200. It will have a useful life of five years and no residual value. It is estimated that the annual variable manufacturing costs will be reduced from $23,200 to $19,300 if the new machine is purchased. The five-year differential effect on profit from replacing the machine is a(n)

a.increase of $53,170

b.decrease of $53,170

c.decrease of $40,900

d.increase of $40,900