Which geological period is called the Age of Fishes? The Weekend quiz

The questions
1 Which existentialists share a grave in Montparnasse Cemetery?
2 Acqua alta is a problem in what Italian city?
3 Which world leader played cricket for Sussex?
4 Which geological period is called the Age of Fishes?
5 Bull-leaping was an ancient ritual on which island?
6 What is a Dutch cabbage salad better known as?
7 What unit was based on the distance from the elbow to the fingertip?
8 Which singer is rerecording all her old albums?
What links:
9 German spa; American Samoa capital; New York prison; Society island?
10 Robot; clone; butler; private investigator; painter?
11 Maritimus; arctos; americanus; thibetanus?
12 Defunct Sunday tabloid; myocardial infarction; Marx Brothers films; bebop?
13 Christiania; Sealand; Seborga; Kugelmugel?
14 Pope (2); Shakespeare (24); both (1)?
15 Space Force; Coast Guard; Army; Marine Corps; Navy; Air Force?

The answers
1 Simone de Beauvoir and Jean-Paul Sartre.
2 Venice (peak tides).
3 Imran Khan (now Pakistan PM).
4 Devonian.
5 Crete (Minoan).
6 Coleslaw (koolsla).
7 Cubit.
8 Taylor Swift.
9 Repeated place names: Baden-Baden; Pago Pago; Sing Sing; Bora Bora.
10 Narrators of Kazuo Ishiguro novels: Klara And The Sun; Never Let Me Go; The Remains Of The Day; When We Were Orphans; An Artist Of The Floating World.
11 Scientific names of bear species (ursus…): polar; brown; American black; Asian black.
12 Albums by Queen: News Of The World; Sheer Heart Attack; A Day At The Races & A Night At The Opera; Jazz.
13 Micronations: Copenhagen; North Sea off Suffolk; Italy; Vienna.
14 Moons of Uranus: sources for names.
15 Six branches of the US armed forces (since 2019).