A manufacturer of exercise equipment purchases pulleys from a supplier who lists these prices: less than $1,000,$ $$5$ each; $1,000$ to $3,999,$ $$4\mathrm{.}95$ each; $4,000$ to $5,999,$ $$4\mathrm{.}90$ each; and $6,000$ or more, $$4\mathrm{.}85$ each. Ordering cost is $$50$ per order, annual holding cost is $20$ percent of purchase cost, and annual usage is $4,900$ pulley. Determine the order quantity that will minimize total cost.