Two fundamental issues underlie inventory planning. These two issues are:

Question $2$Answer

a$.$

the amount to order and when to order

b$.$

the use of a fixed order quantity or fixed order period inventory approach

c$.$

the use of a safety stock and the allowance of a backlog or stockouts

d$.$

independent demand and dependent demand

e$.$

satisfying $100\%$ of demand or requiring demand dependence