Witr and Nawaafil

Q: If fifteen minutes are left for Asar azaan time, and the person has to perform zohar prayer, should he pray fardh only or complete salah with four rakaats and two rakaats sunnah?

Q: I overslept and was late awakening for the fajr Salaah. Thinking it to be very late, I prayed wudhu and only the two fard of Fajr. However after reading this, I checked the perpetual calendar and realised there was still 11 minutes before sunrise. I immediately prayed both my sunnah and my fard of fajr, with 3 minutes still left for sunrise. Was this correct of me? What should I have done in this situation. Is my salaah valid?

Q: I want to know is it compulsory to sleep before performing tahujjud Salaah? If a person is awake till 3 am, can he/she then perform the Salaah? I have heard from many people that it's necessary to sleep before.

Q: In the Hanafi Mazhab, is it permissible for the Imaam to recite qunoot-e-naazilah in all jahri Salaah or is it only permissible for him to recite it in Fajr Salaah?

Q: My question is regarding witr Salaah. In one Hadith the prophet (Sallallahu Alayhi Wasallam) forbade praying witr like maghrib but in the hanafi fiqh it is prayed like maghrib and I am a bit confused. Please clarify.

Q: Is it permissible to read Nafl Salaah sitting on a chair and ruku and sajdha in Ishaarah?

Q: Can we pray one rakaat witr Salaah? Is this Salaah valid?

Q: If one has missed the four Sunnah before zuhr and one reads it afterwards, should one read the two sunnah of zuhr first or the four sunnnah that one has missed first?

Q: Can you please brief me on the different ways to praying witr salaah? and what is the niyah we make for the first two rakaah when we pray two rakah then one rakaah witr. Moreover, is it okay after returning to standing form (after ruku) we raise our hand reciting Dua Qunut and make dua.

Q: What is the Sunnah method of making Istikhaara?