As the managing partner of Whispering Accounting Services $($HAS$),$ Adam is trying to compare the profitability results of the firm's

three different business lines: Audit, Tax, and Advisory Services. These three operating divisions are supported by three support

departments: Billing, Human Resources, and IT$.$ The cost drivers $($or allocation bases$)$ for each of the support departments, along with

each department's usage of those services and its own original costs, are as follows.

$($a$)$

Rank the three support departments by their original costs, and then allocate the support department costs using the step

method. $($Round intermediate calculations to $4$ decimal places, e$.$g$.15\mathrm{.}2516$ and final answers to $2$ decimal places, e$.$g$.15\mathrm{.}25.)($b$)$

Rank the three support departments based on the percentage of their service provided to other support departments, and then

allocate their costs using the step method. $($Round intermediate calculations to $4$ decimal places, e$.$g$.15\mathrm{.}2516$ and final answers to $2$

decimal places, e$.$g$.15\mathrm{.}25.)$