Of the 3 addresses that the game asks you for (network, broadcast, and router interface), what the heck is the router interface address? I have no idea what they mean by that.
The router interface address will be a useable ip in the subnet range, normally you use the first or last ip in that subnet but its your choice
So in your example you are using a /26 mask (255.255.255.192)
This gives you subnet block sizes of 64 eg multiples of 64:
192.168.1.0 - 192.168.1.63
192.168.1.64 - 192.168.1.127
192.168.1.128 - 192.168.1.191
.....and so on.
Using the first subnet 192.168.1.0:
Network address is 192.168.1.0
Broadcast address is 192.168.1.63
Useable IP's: 192.168.1.1 - 192.168.1.62
The router Interface address could be any IP in the useable range .1 - .62 but I would use .1 or .62 being the first and last addresses.
Hope that helps
In terms of exam testing, how good is good enough on the subnet game? Is getting to level five good enough in terms of having the required skills for passing subnetting on the exam?