True: Friction depends on the types of surfaces involved and how hard the surfaces push together.
Answer:
Option C
Explanation:
According to the question:
Force exerted by the team towards south, F = 10 N
Force exerted by the opposite team towards North, F' = 17 N
Net Force, 

Thus the force will be along the direction of force whose magnitude is higher
Therefore,
towards North
Answer:
yes
Explanation:
because it is independent of eachother
·The acceleration of gravity is proportional to
1 / (the square of the distance from the center) .
When we're on the surface, we're 1 radius from the center of the Earth,
and the acceleration of gravity is 9.8 m/s² .
The boy's weight = (mass) · (gravity) = (50kg) · (9.8 m/s²)
= 490 newtons .
At the distance of 5 radii from the center (4 radii altitude from the surface),
the acceleration of gravity is
(9.8 m/s²) · (1/5)² = 0.39 m/s² .
The boy's weight is (mass) · (gravity) = (50kg) · (0.39 m/s²)
= 19.6 newtons .
Just as we expected, his weight at that distance is
(19.6 / 490) = 0.04 = 1/25 = 1/5² of his weight on the surface.