Feather Friends, Inc., distributes a high-quality wooden birdhouse that sells for $80 per unit. Variable expenses are $40.00 per unit, and fixed expenses total $180,000 per year. Its operating results for last year were as follows:

Sales $ 2,080,000

Variable expenses 1,040,000

Contribution margin 1,040,000

Fixed expenses 180,000

Net operating income $ 860,000

If this year's sales increase by $57,000 and fixed expenses do not change, how much will net operating income increase? (I thought it would increase by $28520 but I must be missing something.