I`m a Muslim woman and have fallen in love with a Christian man. Supposing that he embraced Islam. Is it permissible that he proposes to me?
Praise be to Allah the Lord of the Worlds. May His peace and blessings be upon our Prophet Mohammad and upon all his family and companions.
The relationship between you two is forbidden; however, if he wants to embrace Islam then he should pay a visit to a Sharia court. Once he becomes a Muslim, we will address the matter of proposing to you. And Allah The Almighty Knows Best.
Is it obligatory for a wife who has been abandoned for many years to observe the waiting period (iddah) after her husband passes away?
If her husband passes away, the wife is required to observe the waiting period (Iddah), even if he had abandoned her, because she is his wife and inherits from him, so she must observe the iddah after his death. And Allah Knows Best.
Is it permissible to swear by (Allah "The Living")?
Yes, it is permissible because "The Living" is one of Allah`s Attributes.
What is the Islamic ruling regarding a person finding buried treasure, whether gold or artifacts, and what is their share of it?
If the buried treasure is Islamic, it is considered Luqta (lost property), and the finder must announce it to locate its owner. If all efforts to find the owner fail, the finder may take ownership of it. If the treasure is non-Islamic and consists of gold or silver, zakat must be paid on it, which is one-fifth of its value. And Allah Knows Best.