Is it permissible for a woman to ride a taxi without a Mahram (unmarriageable kin) in order to attend a gathering of knowledge?
It is permissible for the woman to pursue the knowledge that she needs in order to perform the religious requirements due on her if there was nobody to teach her at home, provided that there is no temptation involved. Moreover, we don`t recommend that she rides a taxi without a Mahram although such an act isn`t from the forbidden Khulwah (seclusion).
Is it permissible to offer condolences to a non-Muslim?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah.
It is permissible to offer condolences (Ta'ziyah) to a non-Muslim upon the death of their relatives. This constitutes a form of benevolent treatment (Birr) that we have been commanded to observe. Allah Almighty states {what means}: "Allah does not forbid you from those who do not fight you because of religion and do not expel you from your homes—from being righteous toward them and acting justly toward them. Indeed, Allah loves those who act justly." (Surah Al-Mumtahinah, 60:8). And Allah Almighty knows best.
What is required of a traveler or a sick person if they broke their fast and then their excuse ceased?
If a traveler settles or a sick person recovers after having broken their fast, it is recommended for them to refrain from eating and drinking for the rest of the day, but it is not obligatory.
Is it permissible to sleep before the time of the Fajr prayer begins, with the intention of waking up shortly afterward?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah.
It is permissible for a Muslim to sleep before the time of the Fajr prayer begins, intending to wake up and perform the prayer, by setting an alarm or asking someone to wake him. What is to be avoided is that a person sleeps while he predominantly assumes that he will not wake up for the prayer.
If he does not wake up until the time of the prayer has ended, he must make it up. It is recommended that he hasten to make it up as soon as he wakes, and likewise recommended that he make up its sunnah along with it.
It is stated in al-Majmūʿ by Shaykh al-Islām Imam al-Nawawī (may Allah have mercy on him): “Whoever was obliged to pray and did not pray until the time passed must make it up, because of the saying of the Prophet (peace and blessings be upon him): ‘Whoever sleeps through a prayer or forgets it, let him pray it when he remembers it.’ It is recommended that he make it up immediately, because of the ḥadīth we have mentioned. If he delays it, that is permissible, because it is reported that the Prophet (peace and blessings be upon him) missed the Fajr prayer and did not pray it until he had left the valley. Had it been required immediately, he would not have delayed it. Abū Is-ḥāq said: If he left it without a valid Sharia excuse, he must make it up immediately, because he was negligent in delaying it.”
It is therefore the duty of every Muslim to keep the prayer in its proper time, seeking help from Allah the Exalted and striving against the self to do so. And Allah Almighty knows best.