In a barter economy, individual goods are traded for other goods
The answer is B. Ferdinand Magellan because He is the person the modern world credits with first circumnavigating the earth, but it is likely others did it before him. Hope that helps!
How the timeline began from start to continuing from the event you want to start from.
Marbury vs. Madison is the case that established Judicial Review
At any moment if the president is impeached or dies the Vice President will be the next in line.