Permissible and impermissible items of trade

Q: I wanted to know if Crypto Mining is halaal?

Are we allowed to invest in it? If we earn money from mining, is the money above what we invested halaal?

Q: Is it permissible to sell half niqaabs where eyebrows and forehead are exposed just to encourage sisters in their journey of covering the face ? (because a lot of times in the beginning it's hard for sisters to take a full niqaab).

Q: I want to ask you about the permissibility of trading, in crypto currencies, normal currencies and trading in stocks, in Islam.

Q: I have a family person who is unemployed and sells drugs to support his family. Can we go over and have supper by him? Is the food haraam?

Q: I am a young mom and don't work because of my little one. My husband isn't earning much so I recently started a business from home to at least fullfil my own needs. I sell online women's western clothes like skirts, cropped tops, jeans, etc.

I invested some money in it (my small savings I had) but the other day a thought came to my mind if it's halaal to sell such kind of clothes. Having said that most of my customers are Christians. Can you please help me if it's okay to sell such clothes to non-Muslim women?

Q: Can one sell wigs, fake nails and fake eyelashes?

Q: Since eggs can be bought from people who keep free range chickens, won't it be haraam to buy eggs from the shops who get the eggs from the big companies who keep the poor chickens in small boxes their whole life and they keep them very opressively?

Q: Are we allowed to sell pig feed?

Q: Is it permissible to sell water in the following scenario: you have a private meter for your municipal water and you sell this water to your neighbours and tenants at a higher price than what the municipality is charging you?

Q:

1. Is it permitted to sell books authored by Salafis? This is specific regard to books on Hadith and Aqeedah.

2. What is the status of the income earned?

3. Is there a difference in selling to Ulama and non-'Ulama?

4. If a person sells Salafi authored books, does this count as a compromise in Usul/Aqeedah?