Does it extend the signal of a free WiFi?
Parks at a local town provides free WiFi. It requires no password to use. But at some area the signal is very weak. Can I use the extender to make the free WiFi stronger?
Not unless you have access to the router that is providing the wifi. You would need to access the router every time you wanted to use the extender. If you're an owner/employee trying to extend the range, you probably could, but as a citizen, probably not.