Please solve the following problems related to Inventory Management

A produce distributor uses $5400$ packing crates per year. The manager has assigned an annual carrying cost of $$5$ per crate. Ordering cost is $$80.$

$($a$)$ How much is the order quantity based on EOQ model?

$($b$)$ How much is the total cost using EOQ model?

A lab orders a number of chemicals from the same supplier with the lead time two weeks. The assistant manager of the lab must, determine how much of one of these chemicals to order. Usage of the chemical is appropriately normal with a mean of $15$ ml per week and a standard deviation of $5$ ml $.$ The lab management decides that the desired service level for this chemical is $95\%.$

a$)$ What is the average amount of safety stock of the chemical?

b$)$ How much chemical should he ordered?