Janet, it is very simple.
You can use the IP 172 thru 176 to configure your Tenor, which ever you like, just pick the one you like, you have 5 ip to choose from.
The default gateway is 171 and your subnet mask is 255.255.255.248.
Forget about the 171 and 177.
I hope you are not as confused as you were before.
Good luck!