Permissible and impermissible items of trade

Selling a TV

Q: I would like to know the masala regarding the selling of a television. One no longer has the use of a TV and wishes to sell it. Please advise as to which avenues that wealth could be spent in e.g. sadaqah etc?

Giving secular tuition and selling secular textbooks and notes

Q:

1. Is it correct to give tuition to students studying at secular universities? It would involve a male giving tuition to other males only.

2. Is it correct to sell the notes, past papers and textbooks etc. for certain subjects at secular universities?

3. Is it correct to sell the notes, past papers and textbooks etc. for certain subjects at secular correspondence universities (like Unisa)?

All three questions above relate to permissible subjects viz., mathematics, accounting and computer programming.