Is it permissible for a woman to sit with her brothers-in-law?
It is impermissible for a woman to sit with her brothers-in-law, and it is also impermissible for a person to have a Khulwa (seclusion) with his sister-in-law.
What is the ruling o associations (Whereas a person who have money buys a commodity for a person and and gets a profit on it)?
It is permissible for a person to buy a commodity for someone's else and have a profit/loss on it
Is it permissible to fish on Saturday?
All Perfect Praise be to Allah, The Lord of The Worlds, and may His Peace and Blessings be upon our Prophet Muhammad and upon all of his family and companions.
It is permissible for Muslims to fish on any day, but the sons of Israel are the ones forbidden to fish on Saturday. Moreover, there is no evidence in Islamic Sharia prohibiting Muslims from fishing on that day. And Allah Knows Best.
An Imam stood to offer a fifth Rak`ah in a four-Rak`ah prayer, and he was reminded to sit by those behind him, but he wouldn`t listen. What is the ruling on those who followed his lead knowingly and intentionally?
If the Imam stood to offer a fifth Rak`ah, those praying behind him shouldn`t have approved of that, and the prayer of those who did is considered null and void.