The following sales and cost data $($in thousands$)$ are for two companies in the transportation industry:

Required:

$1-$a$.$ Calculate the degree of operating leverage $($DOL$)$ for each company.

$1-$b$.$ If sales increase from the present level, which company benefits more?

Assume that sales rise $15\%$ in the next year but that everything else remains constant. Calculate the percentage increase in profit for

each company.