Question 17 Using the information below, determine the nature of the below costs under variable costing: 4 pts Indirect materials ($.20 a unit) [Select] Indirect Labor (salary) ($90,000 a year) [Select] considered to be a Period Expense. considered to be a Period Expense. Indirect Labor (hourly) ($15 an hour) [Select] considered to be a Period Expense. Maintenance supplies ($12 per unit) is considered to be a Period Expense.