Robin Company has the following balances for the current month:
Direct materials used $ 10,500
Direct labor $ 21,000
Sales salaries $ 15,230
Indirect labor $ 2,890
Production manager's salary $ 4,950
Marketing costs $ 10,000
Factory lease $ 4,400
What is Robin's total manufacturing overhead?
a $31,500
b $17,840
c $12,240
d $10,000