a)Spict Span Ltd is estimating it's fixcd and variable costs. The following costs were incurred in January 2022 when 320 homes were cleaned Cleaning supplies sh.3500 Hourly Wages 5000 Depreciation (cleaning machine) 800 Marketer's salary 2000 Insurance 500 Travelling allowance 1800 Rental expense 1000 Required: i) Determine the cost function;​