Mujtahid

Mujtahid refers to a jurist who performs independent reasoning in finding a solution to a legal question.

What type of knowledge is necessary for someone to become a Mujtahid? Zaid Alsalami	Can you provide information on whether it is written in Quran and Hadith that a Mujtahid should be alive, or if this is a rule made by scholars? Additionally, could you explain the disadvantages of following a dead Mujtahid? Sayyed Mohammad Al-Musawi
Who is the most learned Mujtahid these days whom I can do Taqleed of? Sayyed Mohammad Al-Musawi	Who is the most learned Mujtahid after Sayyid al-Sistani and how can I contact him? Sayyed Mohammad Al-Musawi