Based on the clue 'a deuterium atom is a hydrogen atom that has this ...', what is the answer?

Based on the clue 'a detailed verbal account of an event not necessar...', what is the answer? What is associated with: a detective looking back in regret on leads he should have followed up knows the cliche this i… What is associated with: a detroit arena named for this heavyweight boxing champ was the site of the 1980 gop natl conv… What is associated with: a detroit red wing from 1946 to 1971 it was his records that gretzky broke? Based on the clue 'a deux translates as this', what is the answer? Based on the clue 'a devastating 17th c plague epidemic on this islan...', what is the answer? What is associated with: a devastating forest fire swept through peshtigo wisconsin on the very same day in 1871 as thi… What is associated with: a devastating invasion by these asian warriors in 1241 killed half of hungarys population?