https://docs.google.com/presentation/d/1edzS7jSk8OLVel-IUog-2YW_1iDeBWurDWcLDbV296w/edit?usp=sharing

https://docs.google.com/presentation/d/1ua_R64vnpN4ndsgGbakQ_JROqH4k8A-u112oYuU0TSU/edit?usp=sharing