Sully Company provided the following information for last month. Production in units 3,000 Direct materials cost $7,000 Direct labor cost $10,000 Overhead cost $9,600 Sales commission per unit sold $4 Price per unit sold $29 Fixed selling and administrative expense $7,000 There were no beginning and ending inventories. What is gross margin for Sully Company last month? a.$54,000 b.$47,400 c.$32,400 d.$60,400 e.$64,600