Should missed Sunnah prayer be made up?
Making up missed voluntary acts of worship is from Sunnah.
Is it permissible to give Zakah (obligatory charity) to one`s poor sister, or brother?
It is permissible for one to give the Zakah to his poor sister, or brother if providing for them isn`t due on him, and the sister doesn`t receive sufficient provision from whomever that is due on. And Allah Knows Best.
Is it permissible for a Muslim woman to uncover her hair in the presence of a Christian woman?
All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallahu ‘alayhi wa sallam, is His slave and Messenger.
According to the reliable opinion of the Shafie School of Thought, this isn`t permissible. However, some scholars stated that it is permissible for a woman to uncover what she usually uncovers while doing housework, but this differs from one place to another where some women uncover their hair while some don`t. However, this is provided that a woman doesn`t uncover her hair in the presence of non-Mahram men (Men permissible for a woman to marry). And Allah The Almighty Knows Best.
What is the ruling on performing Umrah after the latest expansion of the Mas`aa (the passage between As-Safa and Al-Marwah), is it permissible, or not?
Yes, it is permissible to perform Umrah after the latest expansion of the Sa`y area since making Sa`y between As-Safa and Al- Marwah is already observed. And Allah Knows Best.