Does the clipping of nails nullify ablution?
No, it does not, and it is preferable to wash the hands afterwards.
What is the ruling on discharges two or three days before the expected period of menstruation and the light-colored blood accompanying it? Must the woman abstain from prayer during this period?
If the total duration of these blood-tinged discharges reaches a day and a night (24 hours) or more, it is considered menstruation. If their total does not exceed 24 hours, it is not considered menstruation but is irregular bleeding (dam al-fasad). Each woman has specific cases for which she should ask the scholars. And Allah the Almighty knows best.
Is it correct that everything dry is pure even if it has impurity on it?
If something impure becomes dry, it remains impure and is not purified by drying. However, the impurity does not transfer by touching it if the one touching it is also dry. And Allah the Almighty knows best.
Is the father a Mahram (Non-marriageable) to his son`s mother-in-law?
The father is a non-Mahram (Marriageable) to his son`s mother-in-law, so it is impermissible for them to look at each other, or to have a seclusion (Khalwah).
