Selected data for the production department of Roller Manufacturing Ltd is presented below: Estimated overhead cost per year $280,000 Estimated direct labour cost per year ($15 per hour) is $300,000 Actual manufacturing overhead for May $24,000 Actual direct labour cost for May (1800 hours) is $25,560 Assume that direct labour hours is the basis for allocating manufacturing overhead. By what amount is manufacturing overhead under or over applied during May? Select one: O a. $1200 under applied O b.$1200 over applied c. $667 under applied O d. Neither under or over applied e $3000 over applied