A company decides to establish an EOQ for an item. The annual sales volume $($demand$)$ is $100,000$ units, each costing $$5,$ ordering costs are $$20$ per order, and inventory carrying costs are $10\%.$ Calculate the following:

a$)$ The EOQ in units

b$)$ Number of orders per year

c$)$ Cost of ordering, cost of carrying inventory, and total cost.