PS 16, 17 , 18, 19 ,20

Q16 - Question
https://goo.gl/forms/uHgTOVJKMNqkI2W92

Q16 - Answer
https://docs.google.com/spreadsheets/d/101GpKINA6IDAtbKfD3i87DxyV5twfxEqwr9H-Kmx72s/edit?usp=sharing

Q17 - Question
https://goo.gl/forms/7f7Uc8QT9qQ1eDde2

Q17 - Answer
https://docs.google.com/spreadsheets/d/1CWF-agTWu699M6uBJUbYjamYVq7WVafLLiGeOLFhxSk/edit?usp=sharing

Q18 - Question
https://goo.gl/forms/V2uMvOHP3IYM7Ou63

Q18 - Answer
https://docs.google.com/spreadsheets/d/1jdlB-ToPwNA1bz7iQCuNJa3svwPn6hxhZ-xcXm9KP18/edit?usp=sharing

Q19 - Question
https://goo.gl/forms/nHjEhBywSKBYut0B2

Q19 - Answer
https://docs.google.com/spreadsheets/d/1Kzzfu7CJXMAV_goxYoJzMHZiEhq9nJNHE1uXK3UhjdA/edit?usp=sharing

Q20 - Question
https://goo.gl/forms/FnU9CyIARLdMuyZa2

Q20 - Answer
https://docs.google.com/spreadsheets/d/1nyZdiv325a4GhKmUTTidtGsdJMXb3n_vtjNORN6Oe2k/edit?usp=sharing