Is it permissible to pay the expiation of an oath to a charitable party as it feeds the poor and needy such as Tkiyet Um Ali?
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.
There is no harm on authorizing someone to handle the expiation of another to the poor and needy, since Shafiee's jurists stated that authorizing someone for the purpose of distributing Zakah, expiation and vow is permissible as stated in [Mughni Al-Muhtajj, vol.3 pp.237]. At last, the intention of the person who intends to authorize someone else suffices in this regard. And Allah Knows Best.
Is it permissible for a Muslim woman to wear trousers at home?
All Perfect Praise is due to Allah, The Lord of The Worlds
Is it permissible for the man to put on revealing clothes? Answer: It is impermissible for the man to put on revealing clothes that show his Awrah(private part) which is between his navel and knee, and exercising modesty is better. And Allah Knows Best.
Is Zakah(obligatory charity) due on articles of merchandise even if they were stacked in the merchant`s stores for years?
Yes, Zakah is due on stored articles of merchandise even if they were stacked in the merchant`s stores for years because this is the way Islam has countered monopoly.
Is it permissible for men to wear silver bracelets and necklaces?
All Praise is due Allah, The Lord of The Worlds
Men are allowed to wear silver rings, but they aren`t allowed to wear bracelets and necklaces because they imitate women by doing so. And Allah Knows Best.