Walker Co. makes three products in its factory: plastic cups, plastic tableclothes, and plastic bottles. The expected overhead costs for the next fiscal year include the following. Factory manager's salary $130,000 Factory utility cost 60,500 Factory supplies 28,000 Total overhead costs $218,500 Walker uses machine hours as the cost driver to allocate overhead costs. Budgeted machine hours for the products are as follows: Cups 420 hours Tablecloths 740 Bottles 1,140 Total machine hours 2,300 Required a. Allocate the budgeted overhead costs to products. b. Provide a possible explanation as to why Walker chose machine hours, instead of labor hours, as the allocation base