Answer:
Rebellions and Power Struggles
Explanation:
Many countries that used to be owned by Spain rebelled and won freedom that way, while other territories were captured and some were just given up on after Spain began to fade into the background after being a world power for so long.
The splitting of north and South Korea
The forceful movement of air.
Primary sources are anything that is from that time period and that date,such as, letters, journals, and photographs(from that time).