I need to know what software and hardware to upgrade from what I have

A department store plans to upgrade its IT infrastructure to support a new order-processing application with rich features. The store currently uses eight stand-alone computers when customers check out. The specifications of these computers are:

Pentium processor
4 GB hard disk
128 MB RAM
Windows 98


The management of the store wants to upgrade four of the computers and use them to process client orders. The initial study done by the management reveals that the computers will perform the following tasks:

.Run an order-processing application that requires a multiprocessing operating system. The application will take orders from customers over the Internet, process the orders, and create invoices.

.Communicate with customers using e-mail to resolve customer queries.

.Store customer data on the local computer. The store will use this data to promote new products.

The department store needs me to upgrade the four computers. I need to find the necessary equipment from online vendors to upgrade the computers.