Various masaail of Salaah

Q: Is it permissible to perform salaah while having cigarettes and currency (since they have picture on them) in one's pocket?

Q: Could you please advise me on some english books and some guidelines on how to perfect your salaah to the highest level?

Q: If the Imam recites Qirat by mouth and there is only 3 lines (saffs) of musallees and the sound by mouth reaches till the 20th line (saff), but still he recites qirat using the microphone and the sound of the loud speaker reaches 5 decibles which can be heard in the building beyond the mosque. The sound level for the 1st line (saff) of musallees is about 95 decibles (dB).

1. Though the mouth is enough, still using the mike and loud speaker, is it tasarruf?

2. When the sound level (dB) goes up beyond the permissible limit (60 dB) what should we do?

3. During the Fajr prayer when the qirat is going on so loudly, it is very difficult to pray sunnat of Fajr.

4. Though the mouth is enough, still using the loud speaker, is it riya?

Q:

1. What is the minimum duration for sujood, qaumah and ruku without which salah will be invalid?

2. If one says Subhana Rabbiyal Azeem and Subhana Rabbiyal Aala once only due to time constraints and if leading salah says Sami Allahu liman Hamidah and goes to sujood, would it suffice for salah to be valid or one has to wait for muqtadees to say Rabbana lakal Hamd?

3. If while leading salah, and in ruku the imam feels by the sounds of steps or running to catch the rakat, is it permisible for the imam to prolong ruku to allow them to catch the rakat?

Q: If a currency bill falls out of my pocket on the praying rug with an animate picture visible, would it affect my Salah?

Q: I have been gifted a memory foam musallah. Is prayer permissible on this mat?

Q: Zaid was working outside on the roof of a attic, when it was Salah time instead of coming down from the rooftop, he prayed Salah on top of the roof of the attic with his shoes on, is the Salah valid?

Q: Zaid was working on the roof of an attic. When it was Salah time, instead of coming down from the rooftop, he prayed Salah on top of the roof of the attic. Is the Salah valid? 

Q: Is it correct to say that salaah was the first command (or possibly one of the first commands?) to be given to every single messenger?

Q: Is it permissible to do nafl ruku out of salaah like we sometimes do nafl sajdah?