1. According to sayed Ali al Sistani is it Mustahab to repeat the dhikr “Subhana Rab al a’la wa bihamdi” 3,5 or 7 times?

2. When raising head from sajdah is it recommended or ok to say Allahu Akbar

3. What is the dhikr that we say when we raise our head from the sajdah and stay still before going back down into sajdah

4. Do we say Allahu Akbar before going into the 2nd sujood of each Rakah

5. Is it recommended to combine the dhuhr and asr prayers and the maghrib and Isha prayers or does the sayed say it is better to space them out and pray them each individually?

1- Yes.
2- It is recommended when you stay still, after raising.
3- أستغفر الله ربي و أتوب إليه ( I Ask forgiveness of God, my Lord and repent to Him)
4- Yes, and while you are sitting still.
5- Separating them is better.