salaam

Sunnat Salaah before zuhr

Q: I would like to ask concerning about the 4 raka'at sunnah before zuhr. I heard someone say that there should only be one salaam in the entire 4 raka'at. Then someone told me that there should be 2 salaams, now I'm confused. Which one is correct? or it depends on which madhhab I follow? Please elaborate.

Zikr and Durood

Q:

1. What's the intention of reciting Allahu Akbar and talbiya? Many times in salah and in other dua's though we do agree the greatness with the heart.

2. What are the wordings of Rasoolullah (Sallallahu Alaihi Wasallam) when reciting darood? Is it same what we use to recite in salah and other daroods? When Rasoolullah (Sallallahu Alaihi Wasallam) is reciting and sending darood and salam on himself, so the wording may change right? Please clarify.

3. What are the wordings that are used by Allah and Angels when sending darood to Rasoolullah (Sallallahu Alaihi Wasallam). Can we repeat the same when we are sending?