16. B, the Athenian government lavishly spent the leagues funds improving itself.
19. B, the Battle of Salamis was fought between Athens and Persia. The Athenian ships were able to manuever much better in the narrow strait then the larger bulkier Persian ships.
20. A, the Spartans had a weak navy prior to getting funding from the Persians thus leading to a strategic advantage over the city of Athens.