Laws of Azaan

Q: Kindly tell me what is the difference between Azaan and Iqaamah? Kindly consider this Hadith "The people mentioned the fire and the bell (they suggested those as signals to indicate the starting of prayers), and by that they mentioned the Jews and the Christians. Then Bilaal was ordered to pronounce Adhan for the prayer by saying its wordings twice, and for the Iqama (the call for the actual standing for the prayers in rows) by saying its wordings once. (Iqama is pronounced when the people are ready for the prayer). Sahi Bukhari Volume 1, Book 11, Number 577 in Azaan we saying words twice but in iqamah we saying words once as mentioned in above hadees. Kindly now tell me your answer as per Quran and Hadees.

Q: If one calls out the Azaan before the Salaah time enters, what is the Shar'ee ruling? Will the Azaan be valid or will it have to be repeated?​

Q: I have a friend who calls azaan repeatedly before its actual timings in roads and in restaurants and shops. I told him to not do that but he says calling it is good. Isn't azaan should be called on prayer time only? Please give detail answer whether I am wrong or he?

Q: I have very attentively heard calling of aazan fron different masajid. Most of them pronounce " hayya las salah and hayya lal falah" whereas the correct pronunciation is " hayya alas salah and hayya alal falah". Please comment.

Q: How many alif should a person pull in the word of Allah in Allahu Akbar in azaan?

Q: When we say the Kalimah Laa Ilaha ILLAllah Muhammadur Rasulullah, then can we also say La Ilaha ILLAllah Muhammadun Rasulullah? With the nūn? Because in my local masjid there used to be a muezzin who used to say Ashadu Anna Muhammadun Rasulullah or Muhammadan Rasulullah, and the Imam said he was wrong and it should be said as Muhammadur Rasulullah.

Q: Can we put an Azaan clock in the Musjid if no one is present in musjid to give azaan on time?

Q: Does the Azaan need to be repeated if half the Azaan was given out of the salaah time and half in the salaah time?

Q: What is the shariah rulings in light of (the Quraan and Hadiths) of appointing someone a مؤذن‎‎, (mu’aḏḏin) or someone is regularly call to
prayer (adhan) who is clean-shaven (without any beard)? To my little understanding a clean shaven person fasiq? Am I correct in my assertion?

Q: When a male is performing salaah alone, should he call out azaan and iqaamah before commencing? If neither are necessary, may he recite iqaamah before commencing?