How long Free Wifi spots keep log details? How many computers behind end of IP Address block xx.xx.x

I have two general questions.

*1*

Generally, how long do free wifi hotspots keep logs of sites visited, mac address and your computer details file?

*2*

Generally, how many computers can be behind a given IP address if the IP address is something like

xx.xx.xxx.101

%26#123;computers are behind the "101" end block of an ip address%26#125;

*By the way, I do know

xx.xx.xxx.101 is not a real ip address*

I just need the answer to the "101" question

How long Free Wifi spots keep log details? How many computers behind end of IP Address block xx.xx.xxx.101?ariel

I work at a Cafe that has free wifi and we keep logs for one week