instruction: How old was Dominik Volek when he made his Czech Extraliga debut?
context: Dominik Volek (born January 12, 1994) is a Czech professional ice hockey player. He is currently playing for HC Sparta Praha of the Czech Extraliga.
  
  Volek made his Czech Extraliga debut playing with HC Sparta Praha during the 2014–15 Czech Extraliga season. Volek is the son of former New York Islanders forward David Volek.
response: Dominik Volek was 20 years old. He debuted in 2014 and was born in 1994, so 2014-1994 = 20.