Permissible and impermissible items of trade

Selling a toy which contains music

Q: We have recently received stock of an Islamic toy which we were unaware had music... The toy has many beneficial learning pages such as duas, surahs, Arabic alphabets, etc. but there is a button which plays nasheeds with musical instruments in the background.

Will it be permissible to sell such a toy? If the toy is sold with a note on how to remove the music and if the customer purchases it and chooses not to remove the music wire, will the seller be sinful?

Buying and selling plot files

Q: I want to ask if it is allowed to sell and purchase plot files? The housing society is still underdevelopment and possession of plots is not given to file holders.

(The file is a document issued by a housing scheme developer, against which one can claim a piece of land/plot once development is done, and possession started by the developer)

Selling books with animate objects

Q: I want to sell physical health eBooks that may contain a few images of humans for the purposes of demonstration e.g. a fitness eBook demonstrating how to perform an exercise or movement. Both male and female images are found in the books and at times, a portion of the awrah of the males and females are exposed. However, this is for demonstrational and educational purposes.

What is the ruling on this and if I had earned wealth through selling these books, what is the status of my wealth, is it halaal or haraam?

Selling university textbooks

Q: A common business practice amongst university students is to buy and sell their used textbooks amongst each other (as buying brand new textbooks from the publisher is extremely expensive).

1. Students, along with selling their textbooks, sell the notes that they made and the lecture slides (pdf version) for that module (subject) as part of one 'package'. Our question is regarding the permissibility of selling the lecture slides - which the lecturer uploads online during the course of the semester - as some naive first year students are unaware that they will be getting them for free over the course of the semester.

2. A lot of textbooks come in an ebook (pdf) format which the publisher sells online (also expensive). It is possible to find a 'pirated' copy of the ebook on the internet and download it. Students also sell these as well at a cheaper price.

2.1 Is this permissible?

2.2 If permissible (2.1), will one get thawaab if one distributes it to students for free instead of selling it to them?