Answer:
1. The central idea is the main idea of a piece of informational text.
2. The following statements are true about a central idea:
- It is supported by the details in the text.
- It covers the whole text.
- It can sometimes be found in the title of the text
3. When determining the central idea of a text, it is important not to confuse the title and the supporting details.
4. The central idea of the passage is: "The Montgolfier brothers theorized that hot air can be used to propel a balloon into flight".