Is a menstruating woman obliged to pray during menses, and should she make up missed prayers?
All perfect praise be to Allah, The Lord of The Worlds A menstruating woman is prohibited from prayer during her menses, and she isn`t obliged to make up missed prayers. And Allah Knows Best.
Is it permissible to make ablution without answering the call of nature after waking up?
Washing front and back openings (Istinjaa`) is not a condition for the validity of ablution because it is done to remove Najaasah (impurity), thus if there is no Najaasah, there is no need for that, and then it is permissible to make ablution without answering the call of nature. However, prayer is invalidated if there is Najaasah on the anus ,or the front opening, so it (Najaasah) must be removed for the prayer to become valid, and not the ablution.
Where should a woman who is led by her husband in prayer stand?
All perfect praise be to Allah The Lord of The Worlds It is from Sunnah (Prophetic tradition) that she stands behind him. And Allah Knows Best.
What is the ruling of Islamic Law on leaving the Sunnah prayer of Dhuhr due to fatigue?
Praise be to Allah, and peace and blessings upon our master, the Messenger of Allah.
According to the general rule, a Muslim should strive to maintain the Sunnah prayers before and after the obligatory prayers (al-sunan al-qabliyyah wa al-ba'diyyah). One is permitted to pray them sitting from the outset, but if one leaves them due to severe fatigue, there is no objection to doing so. It is recommended (mustahabb) to make up (qadā') a time-bound supererogatory prayer (nafl mu'aqqat) at any time if it was missed.
Al-Shirbīnī (may Allah have mercy on him) said: "If a time-bound supererogatory prayer is missed, it is recommended to make it up according to the more authoritative view (al-azhar), based on the hadith recorded in the two Ṣaḥīḥs: 'Whoever sleeps through a prayer or forgets it should pray it when he remembers it.' This is also supported by the fact that the Prophet (peace and blessings be upon him) made up the two rak'ahs of Fajr when he and his companions overslept in the valley and missed the dawn prayer until the sun had risen [narrated by Abū Dāwūd with an authentic chain]." And Allah, the Most High, knows best.