For each item listed below, indicate in the space to the left whether the item would be considered a product cost or a period cost for a manufacturing company. Use the following codes: Pr Product cost Pe Period cost a) Factory supervisory salaries b) Sales commissions c) Income tax expense d) Indirect materials used e) Indirect labour f) Office salaries expense g) Property taxes on factory building h) Sales manager's salary i) Factory wages j) Direct materials used