Adelaide Industries Ltd manufactures a product with the following costs per unit at the expected production of 30,000 units: $ 5 15 Direct materials Direct labour Variable manufacturing overheads Fixed manufacturing overheads The company has the capacity to produce 60,000 units. The product regularly sells for $45. A wholesaler has offered to pay $40 each for 2,000 units If the special order is accepted, the effect on Adelaide's operating income would be a Select one: $24,000 increase. $34,000 increase. $10,000 decrease. $12,000 decrease