The Kerwin Company had the following data (in thousands) for a given period:
Sales ............. $780
Direct materials ......... 180
Direct labor ............ 230
Indirect manufacturing costs .... 210
Selling and administrative expenses . 130

There were no beginning or ending inventories.
Compute the
(1) Manufacturing cost of goods sold,
(2) Gross profit,
(3) Operating income, and
(4) Conversion cost (total manufacturing cost less materials cost).