week 5-https://docs.google.com/presentation/d/1L84TWiMyIb4cepdu0GmgGlP8tginnk1FU_pnFZtMV1w/edit#slide=id.p
week 7-
https://docs.google.com/presentation/d/1JwG_v5c6NmqEU6D0x-jukzcpqsuQTZ5sro5SQvIDpm4/edit#slide=id.g35f391192_00
week 8-
https://docs.google.com/presentation/d/1fjPikhX4zhNbkMFFqkVrBZWscYn2fweClu2HhTYBImA/edit#slide=id.g35f391192_04