Is it permissible to continue working in a store that sells music tapes to provide for the family's needs, knowing that no alternative work with the same income is available?

If the songs contain music, or are performed by female singers, or include meanings that call for vice and incite the forbidden, then selling them is not permissible. This is because when Allah prohibits something, He also prohibits its price. Furthermore, selling them is considered aiding in sin and transgression. Therefore, a Muslim must fear Allah and abandon the forbidden. And whoever gives up something for the sake of Allah, Allah will compensate him with something better.