Danson & Highsmith LLC expects the following results for the next accounting period: Sales $372,000 Variable costs $189,720 Fixed costs $167,780 4,650 Expected production and sales in units The sales manager believes sales could be increased by 800 units if advertising expenditures were increased by $13,000. If advertising expenditures are increased and sales increase by 800 units, the effect on operating income will be a(n) Decrease of $18,360. Decrease of $40,080. Increase of $18,360. Increase of $40,080