How do each of the presenters engage their audiences? What do they do that is similar? How do they differ?

Answer the following questions based on these 2 videos:
https://hls.ted.com/project_masters/1257/manifest.m3u8?intro_master_id=2346

Questions:
1. What does John Bohannon think about Power Point presentations? What alternative does he propose?
2. What are three of the things Garr Reynolds thinks make an engaging presentation?
3. How do each of the presenters engage their audiences? What do they do that is similar? How do they differ?
4. What kind of presentation to you prefer? Explain in detail, please.