the computer counted 2,400 as the incorrect answer. do i put parenthesis around it

Oriole Company is considering two alternatives. Alternative A will have revenues of $147,400 and costs of $103,400. Alternative B will have revenues of $163,200 and costs of $121,600. Compare Alternative A to Alternative B showing incremental revenues, costs, and net income. (Enter negative amounts using either a negative sign preceding the number es.-45 or parentheses es. (45)