Answer:
with the release of avengers endgame all of us know very well about iron Man. and he is my favourite superhero.this because iron Man is a superhero which has developed his super powers with his own mind like the repulsors and super flying jet boots and most amazing and iron Man armour.I like him because I think that I can match my part of life with him he is a genius person. he is a Playboy philanthropist as well as billionaire. firstly everyone thought that he always thinks of himself first and then of the other world but in avengers endgame he sacrificed his life for the whole universe which was a great stop that's why my favourite superhero iron Man.
Electromagnetic radiation I believe
Answer:
The word "protracted" means lasting longer than expected, or unusually long, so what protracted most clearly means based on the context of the excerpt is how the time period of celestial motion studies must have lasted unusually long.
