What is the ruling on speaking while relieving oneself?
It is disliked for one relieving himself to speak while doing so, except out of necessity. And Allah the Almighty knows best.
Which hour coincides with the last third of the night?
This hour could be figured out by calculating the number of night hours which start at sunset, and end at dawn break, then the total is divided on three to get the result.
What is the ruling on a woman who takes medication to delay menstruation for fasting?
If a woman takes medication (to delay menstrual period) and does not experience menstruation, her fast is valid. However, she is not advised to do so unless there is a necessity.
If the medication harms her, even potentially, it is forbidden (haram) for her to take it.
Does passing wind from the anus affect ritual purity?
Ablution is nullified by the passing of wind from the anus, but washing the anus is not required as wind leaves no impurity.