Based on the clue 'a deux translates as this', 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 deuterium atom is a hydrogen atom that has 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? What is associated with: a devastating mar 13 14 1941 bombing of a scottish town is known as the clydebank this germani…