The following monthly data are available for the Sumslow Company and its only product:

$\backslash$table$[[$Unit selling price,$$36,],[$Unit variable expenses,$$28,],[$Total fixed expenses,$$91,800,],[$Actual sales for the month of March,$12,600,$units$]]$

The margin of safety $($in dollars$)$ for the company during March was:

Select one:

a$.$ $$9,000$

b$.$ $$21,600.$

c$.$ $$40,500$

d$.$ $$27,000$