Read the following premise and answer if the hypothesis is true.
Serart is a collaboration album by two international Armenian musicians: Serj Tankian ("Ser-"), lead singer of System of a Down, and folk multi-instrumentalist Arto Tunçboyacıyan ("-art"). It was the first release on Tankian's own label, Serjical Strike Records.
Hypothesis:  Serj Tankian was a singer in the band System of a Down.. Is the answer "Yes", "No", or "It's impossible to say"? Respond with only the answer and no additional text.
Yes
Yes.