For the first question, the statement that best describes the difference between the governments of North and South Korea following the Korean War is:
North Korea is communist, and South Korea is democratic.
For the second question, without the context of what the diagram is depicting, it's difficult to select the most appropriate answer. However, if the diagram is illustrating key events or conflicts during the Cold War or related to Korean history, then:
The Korean War would likely be placed in the center of the diagram, as it is directly related to the division of North and South Korea and has significant implications in the context of Cold War tensions.