Covington Corporation purchased a vibratory finishing machine for $20,000 in year 0. The useful life of the machine is 10 years, at the end of which the machine has zero salvage value. The machine generates net annual revenues of $6,000. The annual operating and maintenance expenses are estimated to be $1,000. If Covington's MARR is 15%, what is the future worth of this investment?
a. $34,998
b. $20,607
c. $13,446
d. $30,887