ComputerLand is a distributor of laptop computers and has been offered quantity discounts from the manufacturer. Under the proposed pricing schedule, the unit price of computers is $$1,500$ for quantities between $1$ and $49$; $$1,450$ for quantities between $50$ and $99$; and $$1,300$ for quantities of $100$ computers or more. The annual carrying cost is $15\%$ of the purchase price, the ordering cost is $$200,$ and the annual demand for computers is estimated to be $2,000.$ The number of$.$computers that should be ordered to minimize total cost is