Listed below are costs found in a company which is in the business of manufacturing radios. Assume that within any given period levels of production and sales activity are equal. Required: For each cost item below, indicate whether it would be classified as a variable cost, fixed cost, or mixed cost with respect to the number of units produced and sold, whether it would be classified as a period cost or a product cost for external reporting purposes, and then whether it would be further categorized as direct material, direct labour, manufacturing overhead cost, selling cost, or administrative cost. 1) The plant manager's salary. 2) The cost of heating the plant. 3) The cost of heating executive offices. 4) The cost of printed circuit boards used in the radios. 5) Salaries and commissions of company salespersons. 6) Depreciation on office equipment used in the executive offices. 7) Depreciation on production equipment used in the plant. 8) Wages of janitorial personnel who clean the plant. 9) The cost of insurance on the plant building. 10) The cost of electricity to light the plant. 11) The cost of electricity to power plant equipment. 12) The cost of maintaining and repairing equipment in the plant. 13) The cost of printing promotional materials for trade shows. 14) The cost of solder used in assembling the radios. 15) The cost of telephone service for the executive offices