https://docs.google.com/presentation/d/1K6wfqjnmv66gUl8d2gksyTaJmAqIlwix/edit?usp=sharing&ouid=103287961825121457286&rtpof=true&sd=true 

https://docs.google.com/presentation/d/1766PS0CaMvGDZyCZ3VveNlFpD6u2IPOQ/edit?usp=sharing&ouid=103287961825121457286&rtpof=true&sd=true