Using the high-low method, compute the variable marketing cost per spike set. (Round unit cost to 2 decimal places, e.g. 52.75.)

Variable marketing cost

=__________

January February March April May June Sales Volume Total Marketing Costs 550,912 $82,796 390,836 $76,187 561,256 $83,004 543,000 $82,456 546,536 $82,484 552,672 $82,876