Networking: Hub with BNC

Hi,

i am just triing to build my first Home-Network and got meself a Hub which includes an BNC-connection.
Since one of the computers is about 20-30m away from the Hub i’d like to go with BNC.

Does anybody know which resistance (50/75 Ohm) the cable needs to have and if i need a terminator at the end of the line ?
My docus dont say anything here.

thanks
peter