suppose that Jacob learned about duration$-$based costing after completing the pilot study. According to the plant manager of the phone plant used for the pilot study, the cycle time for the Regular model is $0\mathrm{.}50$ hours and that of the Deluxe model is one hour. Calculate the unit cost for each model using duration$-$based costing. How do unit costs compare to the ABC costs? Which approach would you recommend to Kim?