What are 3 examples of this rock type?

What is the role of institutions in society - do they perform positive functions, or simply work in the interests of the powerful and against the powerless? (a related question here is why do our life chances vary by class, gender and ethnicity)

What happens in puerto rico in 2012 to celebrate the anniversary of clemente's 3000th hit

John lennon and paul mccartney belonged to this group