Please show formulas input in excel and the solver parameters (i.e objective, changing variable cells, and constraints). Please provide a detailed step-by-step description of your proposed solution. Thank you!

A TV manufacturing company uses speakers at the rate of 8000/mo. When it places an order for speakers it incurs a fixed cost of $1200. The monthly interest rate for keeping a speaker in stock is assessed at 1%/mo. The cost of the speaker depends on the order size.If less than 1000 speakers are ordered the cost is $11 each.When the order size is between 1000 and 10,000 the cost is $10.50/unit.For order sizes between 10,000 and 30,000 the cost is $10 per unit. For order quantities between 30,000 and 80,000 the cost drops to $9.50.Beyond 80,000 the cost is $9.25. Determine the optimum order size and time between orders if shortages are not allowed.