Based on the clue 'a decisive victory or change perhaps made with a n...', what is the answer?

Based on the clue 'a deceased statesman displayed to the general publ...', what is the answer? What is referred to by 'a deceit'? What is associated with: a december 1999 storm in this city flooded the basement of the state hermitage museum? What is associated with: a december 2010 news story said this product was angling for prince william who was just 28 as… Based on the clue 'a decorative fish dwelling is often made from this', what is the answer? Based on the clue 'a decorative floral arrangement in the middle of a...', what is the answer? Based on the clue 'a decorative item on a ships prow or a leader with...', what is the answer? Based on the clue 'a decorative ring of feathers around the neck of a...', what is the answer?