Ms$.$ Socks, the manager of Sojagifo Sales Limited is looking to prepare an income statement for the month of December $2023$ using a contribution approach & has compiled the following data:

$\backslash$table$[[$Cost of goods sold,$$,375,000],[$Variable selling expenses,$$,56,000],[$Fixed selling expenses,$$,125,600],[$Sales return department costs,$$,44,224],[$Variable administrative expenses,$$,159,250],[$Fixed administrative expenses,$$,125,400],[$Sales$,$$$,956,000]]$

Ms$.$ Socks knows that the sales return department costs are a mix of fixed & variable costs & has provided the following information for the last $6$ months to assist you.

$\backslash$table$[[,\backslash$table$[[$Number of$],[$sales returns$]],\backslash$table$[[$Cost of operating$],[$sales return dept.$]]],[$July$,25,000,$$$,42,805\mathrm{.}00$