Depending on what kind of coin your mining, if you are mining on altcoins its still worth it without any doubts.
But I think mining on bitcoins is not worth it anymore to be honest.
It depends on the electricity price. If your electricity price is lower than most of the big farms, you can mine.
Totally wrong, you need for considering the difficulty of the every coin in this time, I guess having a different difficulty for mining, but the altcoin is not in the high difficult and I think if it's still profitable in this time without considering about the cost of electricity in your place.