A) Boeing, a leading aircraft manufacturer, is currently working on a custom-built aircraft order. The company incurred direct materials costs of $2,000,000, including specialized components and raw materials, and direct labor costs of $1,500,000, reflecting the skilled labor required for assembly and customization.

i) Given that Boeing applies overhead based on a predetermined overhead rate set at 150% of direct labor costs, determine the total manufacturing costs for the aircraft.

ii) Discuss the rationale behind using a predetermined overhead rate and its implications for cost estimation and control in a job order costing system.

iii) Outline the steps Boeing might take to refine its cost estimation methods and enhance the accuracy of future job cost calculations. Consider factors such as cost drivers, activity-based costing, and technology adoption. (15 marks)