A mail-order house uses 16,175 boxes a year. Carrying costs are 50 cents per box a year, and ordering costs are $91. The following price schedule applies. Click here for the Excel Data File a. Determine the optimal order quantity. (Round your answer to the nearest whole number.) Answer is complete but not entirely correct. b. Determine the number of orders per year. (Round your answer to 2 decimal places.) Answer is complete but not entirely correct