The Following data (in thousands of dollars) have been taken from the accounting records of Rexman Corp for the just completed year:

Raw materials inventory, beginning $160

Raw materials inventory, ending $280

Work in process inventory, beginning $280

Work in process inventory, ending $200

Finished good inventory, beginning $480

Finished goods inventory, ending $640

Administrative expenses $600

Direct labor $800

Manufacturing overhead $920

Purchases of raw materials $480

Sales $3,960

Selling expenses $560

The net income for the year (in thousands of dollars) was?

I know the answer is $800, but where does that answer come from?