$1)$ Saram Lanka makes winch components for its different product lines. The firm$$s operations manager has gathered the following information for the year $2022$: Demand $=20,000$ winch components per year, Ordering cost $=$ $$25$ per order, Holding cost $=$ $$4$ per winch component per year. She wants to calculate the:

a$)$ Economic order quantity

b$)$ Annual holding costs

c$)$ Annual ordering costs

d$)$ Total inventory costs