ACDC Back in Black is 42

This week in 1980 the Rock and Roll world was shaken to its foundations when AC/DC dropped a megaton bomb called 'Back in Black'. New singer Brian Johnson keeps the worls rocking after Bon Scott dies and they never looked back. 50M copies later, we still crank it up. What is your favorite song? (I forgot to mention Shake a Leg!) SOTD is 'You Shook Me All Night Long"