Answer:
1) the $71,000 is considered a sunk cost because it cannot be recovered.
option A yields $32,000 - $24,000 = $8,000 (this is more profitable)
option B yields $5,000
2) the $104,000 is also considered a sunk cost because it cannot be recovered
option A results in $105,500 - $15,500 = $90,000 in costs
option B costs $85,500 (this option is less costly)