so Profit = Revenue - Costs
she charges $231 per acre, she's got 42 acres that means the Timber grower pays her 42 * 231 every year, so that's her Revenue.
Her property tax is 38 bucks per acrea yearly, so her costs for keeping those acres every year is 38 bucks for each and since she has 42, that means 42 * 38 in total costs for all 42 acres.
