Identify whether each of the following costs should be classified as product costs or period (a) (b) (c) (d) (e) (f) Manufacturing overhead. Selling expenses. Administrative expenses. Advertising expenses. Direct labor. Direct materials. Identify whether each of the following costs should be classified as product costs or period (a) (b) (c) (d) (e) (f) Manufacturing overhead. Selling expenses. Administrative expenses. Advertising expenses. Direct labor. Direct materials