Salaah

Q: With the Mercy of Allah, I have recently starting reading all my qadhaa salaah that i have missed since i became baaligh, this being a few years of salaah. I am able to read my fajr qadhaa before leaving for work, then my zohr qadhaa after performing zohr salaah, magribh qadhaa after magribh and esha after esha salaah. I have not been able to fit in my asr salaah as I am aware that one cannot perform any salaah afer asr. However, I have been advised, that if i am performing my qadhaa salaah then i can perform it after asr. Is this correct or permissable?

Q: I heard that Bibi Khadija the wife of Nabi S.A.W died befor making any Salaah. Was salaah at that time compulsory or not? If yes then when was salaah made waajib?

Q: Can we pray in a room without light where I cannot even see my hand. (This is told by barelvi friend that we cannot offer prayer where we cannot see anything. There should be enough light so that we can see the colour of our prayer rugs.)

Q: I have a thobe that is just above my ankles when walking normally. However when I bend down or go in to ruku, the thobe covers my ankles. Is it permissible to wear such a thobe?

Q: Why is the ladies Ruku' different from the males (they only touch the tips of the fingers on the knees), whereas Nabi (SAW) mentioned many warnings against it e.g the Hadith of stealing from Salaat, the Mursal Hadith in Abu Dawud only proves the Sajdah not the Ruku'?

Q: I know that it is a sunnah to read the last 2 nafl of esha salah seated. Should one always do this, or should it be done occasionally only? Does this apply to the nawafil of dhuhr and maghrib as well?

Q: How should a woman perform salaah in jama'ah, if I perform behind my father (if we are on safar)? How do I make niyyah and what do I read in qiyaam, jalsah, qaumah etc. following the hanafi math'hab?

Q: In Ramadhaan, if we are only two people in an apartment, is it better for us to perform witr with jamaat or is it better for us to perform it individually? In other words, during the month of Ramadhaan, does performing witr with jamaat only apply to the situation where one is in the musjid or does it apply to all places?

Q:

1. Is it imperative to read diff rent surats each day in the five salaats? Would salaat be valid if one continuously recites the same surats only.  For example, in the Maghrib salaat each day, one habitually recites sura Falaq in the first rakaat and sura Naas in the second rakaat. 
2. Can Ayatul Kursi be recited in place of a sura in salaat or is it necessary to add at least two ayaats before or after ayaatul Kursi?

Q: If a person makes a sajdah on a warm hat which overlaps onto his forehead, will this be correct?