My problem with this is that your example replies on you already knowing the correct answer, so that you know it's given you the wrong answer and you can go back and try to trick it into giving a different answer. If you're asking it a question to which you don't already know the answer, how would you know if this has happened?

It's ending because it's old. JET has been running since the 80s. It's successor is ITER, which ran into some delays, but is expected to be finished sometime next year.

I never had that floating over the document I was viewing, just in the home tab of the menu, but I did find a way to switch it off. 'File > Preferences > General' has an option to 'disable all features which require an internet connection'. There are also options in there to disable that opening splash screen if you don't want that.

...and expensive enough that you need to be a nobleman or a legendary hero to get it. The cost of the most basic healing potion is enough for a family to eat for a year.