Answer:
2. The metal surface exerts less frictional force because there are fewer bumps and irregularities on it than there are on the concrete.
Explanation:
Frictional force is a force that is exerted between two surfaces in contact with each other. Frictional force always opposes the direction of relative motion of the two surfaces: for instance, for a ball moving along a surface, the force of friction exerted by the surface on the ball points opposite to the direction of motion of the ball.
The magnitude of the frictional force for a ball moving on a flat surface is given by

where
is the coefficient of friction
m is the mass of the ball
g is the acceleration of gravity
The value of
depends on the type of surface involved. In particular, a smooth surface has a smaller value of
, while a rough surface will have a bigger value. In this case, we are comparing a smooth metal surface with concrete: since the metal surface has fewer bumps and irregularities than concrete, it has a smaller value of coefficient of friction, so it exerts less frictional force than concrete.
In Linear motion the swimmer swims
Unless you are a mutant....I don't think you would make it. I'm 5'8" and most people are 6'7" or less. It's bsically impossible to do. :)
1.the sun must be lined up with the moon and earth all must be aligned for this to happen