There are olive trees within the precincts of the mosque, and my father covers the costs of electricity, water, and other needs of the mosque. Is it permissible for him to take the olive harvest?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah.
If trees and fruit-bearing crops are planted in a mosque for the mosque itself, they may only be spent on the mosque’s interests. If they were planted for the public way (musabbalah), that is, for the general public, then any Muslim who enters the mosque may eat from them. If the planter’s intention is unknown, they are treated like those dedicated for public use, wherever custom has so run.
It is stated in Tuḥfat al-Muḥtāj (Vol.6/p.295): “The fruit of a tree planted for the mosque within it is not freely permitted without compensation. Rather, the imam spends its equivalent value on the mosque’s interests. The tree left its planter’s ownership here without any verbal declaration because of the evident indication. The case of planting it for the mosque excludes planting it as musabbalah, in which case eating from it without compensation is permissible, and likewise if his intention is unknown, where custom has so run. The tree may be uprooted from the mosque if the imam sees fit. Indeed, if he makes the plot a mosque while a tree stands in it, the imam may uproot it, even if the endower included it within the endowment (waqf).”
The father is a donor (mutabarriʿ), so he is not entitled to take anything in return for his donation to the mosque.
The Ministry of Awqāf is the body that supervises the affairs of endowments, so it must be consulted and the Sharīʿah and administrative instructions regulating such matters must be considered. And Allah Almighty knows best.
Is it valid to perform Tarawih prayer at home?
It is Sunnah for a Muslim to perform Tarawih prayer in congregation at the mosque.
However, if a person sometimes prays it at home in congregation with their family for a valid reason, there is no harm in doing so.
Are the mother's maternal and paternal uncles, and the father's maternal and paternal uncles, considered among the unmarriageable kin (Maharim)?
Praise be to Allah, and peace and blessings be upon our Master, the Messenger of Allah.
A mother’s maternal uncle and her paternal uncle, as well as a father’s maternal uncle and his paternal uncle, are all considered among the unmarriageable kin (Maharim). And Allah the Exalted knows best.
What is the ruling on vomiting, and does it invalidate ablution?
Vomit is impure (najis). Its exit is not considered one of the nullifiers of ablution. However, the mouth must be washed and purified from it, and any that gets on clothing or the body must be washed for prayer, because prayer is not valid with impurity present on the body or clothing. And Allah the Almighty knows best.