Durable Doors, Inc., produces two types of doors, interior and exterior. The company's simple costing system has two direct-cost categories (materials and labor) and one indirect-cost pool. The simple costing system allocates indirect costs on the basis of machine-hours. Recently, the owners of Durable Doors have been concerned about a decline in the market share for their interior doors, usually their biggest seller. Information related to Durable Doors production for the most recent year follows: The owners have heard of other companies in the industry that are now using an activity-based costing system and are curious how an ABC system would affect their product costing decisions. After analyzing the indirect-cost pool for Durable Doors, the owners identify six activities as generating indirect costs: production scheduling, material handling, machine setup, assembly, inspection, and marketing. Durable Doors collected the following data related to the indirect-cost activities: 1. Calculate the cost of an interior door and an exterior door under the existing simple costing system. 2. Calculate the cost of an interior door and an exterior door under an activity-based costing system. 3. Compare the costs of the doors in requirements 1 and 2. Why do the simple and activity-based costing systems differ in the cost of an interior door and an exterior door? 4. How might Durable Doors, Inc., use the new cost information from its activity-based costing system to address the declining market share for interior doors