music: 70's Chart Toppers: Name The Artist: Birds Of A Feather?

Questions

Greenday performed the song "Good Riddance", what other name is this song known as?

Greg Ridley left Spooky Tooth to join what group?

Group stripped of a Grammy for not doing much more than posing for the cover.?

Group that sang ``Want Ads'', #1 hit on June 12, 1971?

Group whose albums include: "In Heat", "Lysergic Emanations" and "Braindrops"?