Question about Relay and Ports?

1. when u say that it relays it to the other connencted device, does it mean that it SENDS or relates?


2. where are I/O ports attached how can count them. i mean if there r 5 work stations then there must be 5 outputs, 1 for each. how n-1

Yes relays mean to convey, to send.

I/O ports stands for input/output ports. In any topology workstations are connected to server or hub by these ports. So that they can request/send data to server as input and can order/receive data from server as output.
Here in mesh topology "n" is used for nodes. Mean total number of computers in network, including server. As server is doing all processing and send required data to workstations and output will be showed on these work stations so I/O ports will be one less than total number of computers in the network. So if total number of workstations will 5 then i/p ports will be 5,bt in this case there will be 6 nodes including server.