cable modem config

We have two isp lines coming into our building. One a 56K, the other a cable modem. The cable modem is not connected and I would like to connect it. We do not have a server setup, just a frame relay. Can I connect the cable moden to a hub then connect the internet computers we to the hub? If not, what would I need to make the connections so that I can utilize the cable modem. Thanks in advance.