https://docs.google.com/presentation/d/1a5pkKZxo8eFzw9-SluvssB_CYRF-LPZ1WxGf5rrklzI/edit#slide=id.g5c3be0ce2d_1_28
https://docs.google.com/presentation/d/1h2LzkKZl6krxkO5j0mYU6X136-qpm5Bx1SoBN0N11g4/edit#slide=id.g98360a696d_0_83