Witr and Nawaafil

Q: Is it permissible to pray Salaatul Hajaat on behalf of another person and pray to Allah to ease his difficulties?

Q: I am the mukabbir for taraweeh salaah,is this ok?

Q: If one started to perform tahajud salaah, suddenly he remembered he was impure. Does one need to make kazaa for the same?

Q: During weekdays, I perform Zuhar and Asr on the staircase in the office. So, there is not much convenience and hence I miss out zuhur sunnah salaah on a regular basis. And also I perform Zuhr about one hour before Asr time, so that I do not have to do wudu twice. Please advise.

Q: The Mukrooh time for Asr Salaah sets in when the sun looses its glare and one is able to gaze directly at the sun without any hurt to the eye. If this is correct, then will it be correct to apply the opposite  in order to establish the time of Ishraaq? I.e. After sunrise, as long as one is able to look directly at the sun the time of Ishraaq has not yet set in. However, once one is not able to look directly at the sun, can it be said that the time of Ishraaq has set in? Generally we are told that Ishraaq can be made 10-15 minutes after the time of sunrise. However, in some places it has been noticed that after 5-7 minutes (from the time of sunrise stated on the calender) the sun becomes bright enough that one is not able to gaze directly at it. Furthmore, what is the easiest way to determine the time of Ishraaq when the time of sunrise is not known?

Q: We have read qunoot-e-Naazila in Jumuah salaah (for problems in Syria). Is it allowed and is our salaah valid or should be repeated?

Q: I have many years of qadha salaahs. I need to know if I can read my qadha salaah instead of the sunnah salaah. I know that when I am a musaafir, I am exempted from reading sunnah. What about when I am a muqeem? When fardh salaah is more important then sunnah, then please advise if I can read all my fardh qadha salaah in place of my sunnah of zuhr, maghrib and esha.

Q: What is the correct way to perform tahajjud salaah? 

Q: If a person starts reading the four rakat sunnah before the jumaah khutba azan, and azan begins, what do i do? Make it 2 rakats, or read all four rakats? If I start my sunnah before the azan of the khutba, and know that I can finish the full four rakats before the azan ends, can I perform the four rakats?

Q: Can you give the proof and hadith in which the prophet (Sallallahu Alayhi Wasallam) prayed four rakaats sunnah at once. Someone is saying that the prophet (Sallallahu Alayhi Wasallam) prayed them 2 then 2 so can you give the hadith and its strength?