Hopefully this should help you
http://gcc.glendale.edu/fire/Documents/ClassMaterials/Ropes/Ropes-VFA08.pdf
Knots start on page 35
plz thank me, it motivates me to answer more of your questions :)
Physical activity and healthy diet
It should be C. the depth for a compression for a 13 year old is 1 1/2- 2 inches
Answer:
By using S>T>O>P you should first remind your friend how it's not safe to and if they call you a coward just tell them the accidents and how it will affect them and they may regret they're life decisions based on what they are going to do.
Explanation:
As you know doing such stuff may be unsafe and may effect your body by hurting or injurying yourself so tell your friends about how they shouldnt do it without parental supervision of any sort and make sure she wears saftey gears if she plans on actually doing it.