Wages for employees who work directly in production is what type of cost? Odirect labor O selling and administrative expense Odirect materials Ofactory overhead Hourly wages of operators of robotic machinery used in production is what type of cost? Odirect materials factory overhead O selling and administrative expense Odirect labor Depreciation of copying machines used in the Marketing Department is what type of cost? direct labor selling and administrative expense Ofactory overhead O direct materials Cost of advertising in a national magazine is what type of cost? O selling and administrative expense O factory overhead Odirect materials Odirect labor