Is it legal to "use" an unprotected wireless access point that you discover in a public area? is it ethical to use it? hypothetically, if you were at an event and your computer detected a wireless network which was not protected and that was not sponsored by the event or its organizers, would you use it? justify your answer

The legality of use is dependent on the permissions provided by the owner, service provider ad state's laws. It is not ethical to use open wifi not provided or sponsored by event's organizer.

Some of the risk are:

Privacy leak and risk of confidentiality. Wifi data transfer occur using encryption but there are also some devices that can decrypt this data provided the have access the wifi. In open wifi, since everyone has access hence anyone with malicious intents can overlook your activities by decrypting data. This become more dangerous when a person is accessing bank statement or doing transactions on public wifi.

c a goverment agency or homeowner