What are the five improvements to “the science of politics”, according to Hamilton,
that will make the American republic work?

1.  legislative checks and balances, 2. the separation of powers, 3. an independent judiciary, 4. a scheme of representation, and 5. a more recent innovation which Hamilton, the author of Federalist 9, calls “the enlargement of the orbit within which [republican]systems are to revolve."

answer; people where able to travel across the u.s.a faster than any other mode of transportation,travel time was about a week,from coast to coast

b. africa to the americas

explanation: