Mr$.$ Cheung has instructed his chief accountant to prepare a contribution income statement showing the comparison of the actual performance for the year ended December $312021$ with the master budget. The master budget was fixed at the beginning of the year $2021.$ The company's costing system for manufacturing has two direct$-$cost categories $($direct material and direct labour$-$both variable$)$ and two production overhead cost categories $($variable and fixed manufacturing overhead$).$ Assume there were no beginning and ending inventory. The division adopts direct labour hours as the allocation base for manufacturing overhead. The contribution income statement $($ignore nonproduction cost$)$ and other information is shown below.

$\backslash$table$[[,\backslash$table$[[$Contribution Income Statement$],[$Static$],[$Budget$]],$Actual$],[,,],[$Number of units produced and sold,$40,000,46,000],[,$$$,$$