What is the ruling on raising hands and saying "Ameen" aloud, and what is the ruling on invoking blessings upon the Prophet when his name is mentioned during the Qunut supplication in Witr and Fajr prayers?

The disagreement regarding Qunut in the Fajr prayer or Witr is well-known. It is recommended to raise the hands when supplicating for the Qunut. The congregant should say "Ameen" upon hearing the supplication, and should do so audibly. As for invoking blessings upon the Prophet, peace be upon him, it is a Sunnah. Scholars have differed on whether the congregant should say "Ameen" for it or participate in it.