24 a) i What are responsibility centers? Give examples of each type. ii) What is the difference between RI and ROI as performance measurement tools. Explain with a numerical example. (8) b) Arbon Company has three service departments and two operating departments. Selected dara concerning the five departments are presented below: The company allocates service department costs by the step-down method in the following order: Administrative (number of employees). Janitorial (space occupied), and Equipment Maintenance (machine-hours). Requiredt Using the stepdown method, allocate the service department costs to the operating departments