Which musician, Ian Ball or Dave Mustaine, is co-founder of the American metal band Megadeth?
Dave Mustaine: David Scott Mustaine (born September 13, 1961) is an American musician, singer, songwriter, actor and author. Dave Mustaine:  He is best known as the co-founder, guitarist, lead singer, and primary songwriter of the American thrash metal band Megadeth, and the original lead guitarist of the American thrash metal band Metallica. Ian Ball:  He has also performed and released two solo albums (as of June 2017).
i don't know