Alamo Electronics Corporation manufactures a hand dryer designed for mounting on the wall of the bathroom. Required: Classify each of the following different types of costs incurred in the manufacture of these dryers as product cost (inventoriable) or period cost (noninventoriable), for the purpose of preparing external financial statements. Sales commissions. Period cost Production factory wages. Product cost - Property taxes on the factory building. Period cost Sales manager's salary. Period cost Indirect labor. Product cost - Factory supervisory salaries. Period cost Income tax expense. Period cost Direct materials used. Product cost Office salaries expense. Period cost Indirect materials used. Period cost