Potter & weasley company had the following activities, estimated indirect activity costs, and allocation bases: activities indirect activity costs allocation base account inquiry (hours) $ 85.600 3 comma 900 account billing (lines) $ 59 comma 000 31 comma 000 account verification (accounts) $ 39 comma 250 23 comma 500 correspondence (letters) $ 89 comma 000 9 comma 000 potter & weasley uses activity based costing. the above activities are used by departments p and q as follows: department p department q account inquiry (hours) 400 800 account billing (lines) 10,000 4,000 account verification (accounts) 6,000 7,000 correspondence (letters) 1,000 2,000 what is the cost per driver unit for the account billing activity? (round all answers to two decimal places.)