Need help with second part

Demand for doughnut holes on Saturdays at Don's Doughnut Shoppe is shown in the following table. Click here for the ExcelData File a.4. Determine the optimal number of doughnut holes, in dozens, to stock if labor, moterials, and overheod are estimated to be 56.40 per dozen, doughnut holes are sold for $8.00 per dozen, and leftover dowghnut holes at the end of each doy are sold the next doy at half price. (Round your answer to the nearest whole number.) a-2. What is the resulting service level? (Round your answer to 2 decimal places.) \& Answer is complete but not entirely correct