It’s 4, I’m on Plato but I literally just learned about all the ancient civilizations it’s the same thing
While you didn't really provide the "following" as the comment above me states, in general, the advantage of secondary sources of primary ones is that they perhaps provide a more objective or even just a broader view on a certain topic. While a primary source of the American civil war would be a letter written by a soldier, a secondary source would be a book that describes more letters taken together and discusses possible information regarding them.
Inland many writers for tray disillusionment and to reevaluate the myth of American heroes , I hope this helps .
Traveling across the Pacific Ocean would be the longest distance to travel, since it is the largest ocean by square milage, although it would be possible to combine different routes to increase the distance traveled elsewhere.