The magnitude of the frictional force along the plane is most nearly

F = N*μ or F =m*g*μ

Explanation:

The friction force is defined as the product of the normal force by the corresponding friction factor.

When a body is in equilibrium over a horizontal plane its normal force value shall be equal to:

if we simplify this formula more for a balanced body on a horizontal plane, we will have.

a longitudinal wave moves energy that is to the direction of the wave’s movement. - true

reserve is the answer