What is the ruling on making up missed fasts from many years?
A Muslim must make up for any missed fasts, as they are a debt owed to Allah. The Prophet ﷺ said:
"The debt owed to Allah is more deserving of being fulfilled." [Narrated by Muslim]
Whoever has missed fasts must make them up as long as they are alive and capable of fasting.
What is the ruling on water present on the floor of a toilet/bathroom?
The default ruling is the purity of this water present on the bathroom floor. If one is certain or strongly suspects its impurity, then one washes whatever part of the body or clothing this impure water has touched. If one doubts its impurity, the default is purity, and we do not rule it impure based on mere doubt. And Allah the Almighty knows best.
What is the ruling of Islamic Law on shaving body hair and clipping the nails for one who is in a state of major ritual impurity (*junub*)?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah.
It is recommended for one in a state of major ritual impurity (junub) not to remove anything from his body until after the ritual bath (ghusl). It is stated in Bushrā al-Karīm bi-Sharḥ Masāʾil al-Taʿlīm (p. 135): “It is recommended for one in a state of janābah and the like not to remove anything from his body until after ghusl, because the parts of the body return to him in the Hereafter, and he returns in a state of janābah, as a rebuke to him. Then it is removed from him, except for the original parts. It is said that every hair demands its due for its janābah.”
It is stated in Ḥāshiyat al-Shabrāmallisī ʿalā Nihāyat al-Muḥtāj (Vol.2/p.341): “If he wishes to combine shaving and the Friday ghusl, he should delay the shaving until after the ghusl if he is in a state of janābah, so that the ghusl removes its trace from the hair.” And Allah Almighty knows best.
Is it permissible for a woman to lead other women in prayer?
Yes, it is permissible for a woman to lead other women in prayer. The most knowledgeable among them in the rulings of prayer should act as the imam. She should stand in the middle of the row, slightly ahead of the others.