https://docs.google.com/presentation/d/12OEXnlKNbuECUwGyhexlbX-Qj_ZVqB06yWezKSXrHlA/edit?usp=sharing

https://docs.google.com/presentation/d/1Clr3B-7ebBSHYmc3vtF5R7076qrCyI9xTONH78b1buk/edit?usp=sharing