https://docs.google.com/presentation/d/1N9LiqT9fQFWlARVf6OzLjiw-2mP4jt2v/edit?usp=sharing&ouid=107342720656280156391&rtpof=true&sd=true
https://docs.google.com/presentation/d/17cgefs7QHkus32AjXk-c8wY_ImUHZRUj/edit?usp=sharing&ouid=107342720656280156391&rtpof=true&sd=true