Please answer all parts with correct explanations and supporting statement and calculations. Make sure the answer is correct and is not copied from AI.

Problem 12-14 (Algo) A jewelry firm buys semiprecious stones to make bracelets and rings. The supplier quotes a price of $8.20 per stone for quantities of 6500 stones or more, $8.60 per stone for orders of 400 to 599 stones, and $9.10 per stone for lesser quantities. The jewelry firm operates 270 days per year. Usage rate is 20 stones per day, and ordering costs are $49. a. If carrying costs are $3 per year for each stone, find the order quantity that will minimize total annual cost. (Do not round intermediate calculations, except for order quantities which should be rounded to the nearest whole number. Round your final answer te the nearest wheole number.) 'stones b. If annual carrying costs are 31 percent of unit cost, what is the optimal order size? (Do neot round intermediate calculations, except for order quantities which should be rounded to the nearest whole number. Round your final answer to the nearest whole number.) [ [stones c. If lead time is 4 working days, at what point should the company reorder? (De not round intermediate calculations. Round your final answer to the nearest whole number.)