Is it permissible to divide one mudd of fidyah between two people?
No, it is not permissible to divide one mudd between two people, because it would not count as a full meal for either of them.
What is the ruling on using snuff, inhaled vapor, or menthol rub (Vicks) during the day in Ramadan?
Using snuff, inhaled vapor, or menthol rub (Vicks) invalidates the fast because these substances enter the lungs through inhalation, and the lungs are considered part of the body cavity (jauf).
Whoever uses them must refrain from eating and drinking for the rest of the day out of respect for the sacred month and make up for that day after Ramadan.
However, if it is merely a scent and none of its substance reaches the body cavity, it does not break the fast.
Is washing the private part after urinating (Istinjaa`) a condition, and is it done with water and soap, or with water only?
Istinjaa` is obligatory for removing impurity, and it can be done with toilet paper, or a stone, or water. It is preferable to do Istinjaa` first with paper, or stone, or the like, then to wash the private part with water until making sure that the impurity has been removed. Using soap is not a condition, but there is no harm in doing so provided that it is washed off with water. It is also permissible to use either water, or paper if impurity is removed by any.
What is the ruling on the use of an inhaler by a *muḥrim* (a person in the state of *iḥrām*)? [An inhaler is a medicinal device used for inhalation, containing various herbal ingredients.]؟
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah.
It is permissible for the muḥrim (a person in the state of iḥrām) to use incense (bakhūr), sprays, and inhalers that contain aromatic substances for the purpose of treatment, because the intention is medical treatment, not the use of perfume (taṭayyub). No expiation (fidyah) is required of him for doing so.
It is stated in Ḥāshiyat al-Bujayrimī ʿalā al-Khaṭīb (Vol.2/p.455): “That which is intended for eating or for medical treatment, even if it has a pleasant scent, such as apples, spikenard (sunbul), and the various fragrant spices such as mastic (muṣṭakā), is not forbidden, and no fidyah is due for it, because what is intended for eating or treatment carries no fidyah.”. And Allah Almighty knows best.