Misc: What is the element symbol for Actinium?

Questions

1992 - who did the us marine corps honor for 5 decades of entertaining troups??

what does nhra stand for??

who recorded the 1951 hit song "down yonder"??

whose song does weird al yankovic spoof with like a surgeon??

who had a us top 40 hit single called "stairway to heaven" in 1960?