Is it permissible for one who sacrifices on behalf of another, with the latter's permission, to eat from the sacrifice?
It is permissible for someone who sacrificed on behalf of another with their permission to eat from it with their permission, and they stand in their place (act as their representative) in distributing it.
It is stated in Nihayat al-Muhtaj ila Sharh al-Minhaj (Vol.8/P.141): "And he—meaning the one sacrificing on his own behalf, provided he has not apostatized—has the right to eat from a voluntary sacrifice and his sacrificial gift; rather, it is recommended. As for an obligatory sacrifice, it is forbidden for him to eat from it, whether it was designated as such initially or as a liability in his dhimmah. And excluded by what has preceded is if he sacrifices on behalf of another, or if he apostatized, then it is not permissible for him to eat from it, just as it is absolutely impermissible to feed a disbeliever from it."(The text I found indicates the impermissibility of eating) ???
And it is stated in Hashiyat al-Jamal ‘ala Sharh al-Manhaj (Vol.5/P.262): "If a person offers a sacrifice on behalf of a living person with their permission, does he act as their representative in distributing it—on the grounds that permission to sacrifice is permission to distribute it—or does it depend on their explicit permission? This requires consideration, but the first view is not far-fetched." And Allah the Almighty knows best.
If a father stops his daughter from getting married, is it permissible for her to conclude the marriage contract herself?
It is permissible for the father to stop his daughter from getting married if there was a lawful reason for that, and she isn`t allowed to conclude the marriage contract without her guardian. However, if her father denied her right in getting married for an unlawful reason, then she should go to court.
Who is the one deemed "able" (al-qādir), for whom the uḍḥiyah (sacrificial offering) is sunnah?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah ﷺ.
The one who is deemed "able" (al-qādir) [to perform the uḍḥiyah, i.e., the sacrifice] is someone who possesses wealth sufficient to acquire the sacrificial animal, over and above what is needed to cover his own living expenses and the living expenses of his wife and children — or of anyone else whose financial support (nafaqah) is legally obligatory upon him — for the day of ‘Eid and the three days of Tashrīq [that follow it], since this is the designated time period for the sacrifice. And Allah, the Exalted, knows best.
I own a pharmacy and have only merchandise. A full year (*ḥawl*) has passed and I have no cash. How do I pay the zakāh?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah.
Zakāh must be paid immediately from the day it becomes due, and delaying it is forbidden when one is able to pay it, because it is the right of the poor, and it is forbidden to delay giving people their rights except for a valid Sharīʿah excuse. Shaykh al-Islām Imam al-Nawawī (may Allah have mercy on him) said: “In our school, zakāh must be paid out immediately. Once it becomes due and he is able to pay it, it is not permissible to delay it. If he is unable, he may delay it until he is able. If he delays it after being able, he is disobedient and becomes liable for it.” [al-Majmūʿ Sharḥ al-Muhadhdhab, Vol.5/p.333]
If cash is not available to pay the zakāh and the only option is to pay in installments, he must pay it, even if in installments, from the proceeds of the merchandise that is sold after the time the zakāh became due, by deducting a set amount from each day’s takings. And Allah Almighty knows best.