1. A toy manufacturer uses 48,000 rubber wheels per year for its popular dump truck series. The firm makes its own wheels, which it can produce at a rate of 800 per day. The toy trucks are assembled uniformly over the entire year. Carrying cost is $1 per wheel a year. Setup cost for a production run of wheels is $45. The firm operates 240 days per year. Determine the following:

1. Optimal run size (3)
2. Minimum total annual cost for carrying and setup (5)
3. the length of the production run (Run time) (2)