Answer:
If you kick a football and it moves from one place to another, it means that unbalanced forces are acting upon it. Ball moves from one place to another after kicking it. This is an example of unbalanced force.
Explanation:
Air is the answer i do believe
The weight of the person is given by:
W = mg
W = weight, m = mass, g = gravitational acceleration
Given values:
m = 40kg, g = 9.81m/s²
Plug in and solve for W:
W = 40(9.81)
W = 390N
You multiply force times friction