he sales$-$mix variance is calculated by $\_\_\_\_\_\_\_\_.$

deducting budgeted contribution margin based on actual units at actual mix from budgeted contribution margin based on budgeted units sold at the budgeted mix

deducting budgeted contribution margin based on actual units at budgeted mix from budgeted contribution margin based on actual units sold at the actual mix

deducting budgeted contribution margin based on budgeted units at actual mix from budgeted contribution margin based on actual units sold at the budgeted mix

deducting budgeted contribution margin based on actual units at actual mix from budgeted contribution margin based on actual units sold at the actual mix