could someone explain why the answer for this is 1,600? Thank you!

1. Meander Inc. incurred $1,500 in production costs for the week. Work in process decreased by $100, and finished goods inventory increased by $500 during the week. What was the cost of goods manufactured (COGM) for the week? a. $1,100 b. $1,400 c. $1,500 d. $1,600