How come the correct answer is A? Please explain.

7 Our company makes and sells bicycles. We never hold inventories. Last year, our net operating income (NOI) was $800,000. The llowing additional information is available about last year: -192 Amount 36,000 Units Sold Unit Selling Price Product Cost per Unit (under GAAP) Fixed Manufacturing Overhead Variable Selling and Administrative Cost per 26 S 1,440,000 17 Approximately how many units would we need to sell to earn the NOI of $1,600,000? 45.756 72,000 37,073 72,381 E. None of the above