Can someone who begins a voluntary fast break it?
It is preferable for someone who begins an act of worship not to break it.
Allah the Exalted has said {what means}: "and let not your [good] deeds come to nought!" [Muhammad/33].
However, if a person starts a voluntary fast (nafl) and needs to break it, they are going against what is preferable, but there is no sin upon them.
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.
Is it permissible to offer an Udhiyah on behalf of the deceased?
Praise be to Allah, and peace and blessings be upon our master, the Messenger of Allah.
Offering a sacrifice (Udhiyah) on behalf of the deceased is permissible. This is the position of the Hanbalis [Kashshaf al-Qina’ by al-Bahuti (Vol.6/P.428)], and it was held by al-Abbadi of the Shafi’is [Bidayat al-Muhtaj by Ibn Qadi Shuhbah (Vol.4/P.358)]; it is also narrated from some Maliki and Hanafi scholars.
Abu Dawud included a chapter in his Sunan titled "Chapter: Offering the Sacrifice on Behalf of the Deceased," in which he narrated from Hanash, who said: "I saw Ali (may Allah be pleased with him) sacrificing two rams. I asked him, 'What is this?' He replied, 'The Messenger of Allah (peace be upon him) enjoined me to sacrifice on his behalf, so I am sacrificing on his behalf.'"
Abu Dawud also narrated from Jabir (may Allah be pleased with him) that the Prophet (peace be upon him) said: "O Allah, this is from You and for You, on behalf of Muhammad and his Ummah; in the name of Allah, and Allah is the Greatest," then he slaughtered it. It is well known that among the Ummah of Muhammad (peace be upon him) are those who have passed away, yet he (peace be upon him) dedicated it to his entire Ummah.
Furthermore, multiple Sharia texts have consistently indicated that the rewards of righteous deeds reach the deceased. This includes the permissibility of fasting on behalf of the deceased if they died owing fasts, as well as the permissibility of performing Hajj on their behalf, both of which are established in authentic Hadiths. Since the rewards for fasting—a physical act of worship—and Hajj—a physical and financial act of worship—reach the deceased, then the sacrifice (Udhiyah) is even more likely to reach them.
Moreover, the scholars have reached a consensus (Ijma') that the rewards of charities reach the deceased, and the Udhiyah is a form of charity and falls under its general category. Based on all of this, we hold the view that offering a sacrifice on behalf of the deceased is permissible. And Allah the Almighty knows best.
Is bleeding that lasts for nine or ten days considered menstruation (Hayd)?
Praise be to Allah, and peace and blessings be upon our Master, the Messenger of Allah.
If the duration of the bleeding does not exceed fifteen days, then all of it is considered menstruation (Hayd), even if the regular cycle ('Adah) has changed. And Allah the Exalted knows best.
