a-1. Use the high-low method to determine the variable element of manufacturing overhead costs per machine-hour. (Round your answer to 2 decimal places.) a-2. Use the high-low method to determine the fixed element of monthly overhead cost. (Round "Manufacturing overhead cost" to 2 decimal places.) b. Bursa expects machine-hours in May to equal 5,300. Use the cost relationships determined in part a to forecast May's manufacturing overhead costs. (Round "Manufacturing overhead cost" to 2 decimal places.) c. Suppose Bursa had used the cost relationships determined in part a to estimate the total manufacturing overhead expected for the months of February and March. By what amounts would Bursa have over- or underestimated these costs? (Round "Manufacturing overhead cost" to 2 decimal places.)