The short answer (and the long one for that matter) is physical properties of chemicals. If you are being marked by a machine, likely the answer is going to be physical properties.
As we know that spring force is given as

here we know that
F = 4 N
x = 2 cm = 0.02 m
now from the above equation we will have


so the elastic constant of the spring will be 200 N/m
Answer:
Explanation:
Given
mass of squirrel 
Surface area of squirrel 
and the area which face 
height of tree 
Coefficient of drag 
drag Force 
Terminal velocity is given





(b)Mass of person 





At Korona100 I don’t think it’s 10, becz I remember having this question on my test/ quiz but I got it incorrect so yeah.