The statement which is true of a wave that’s propagating along the pavement and girders of a suspension bridge is A. The wave is mechanical, with particles vibrating in a direction that is parallel to that of the wave, forming compressions and rarefactions.
Normal force is the force exerted when an object is on an surface. So an example could be a pile of books on top of a table.
<h2>QUESTION:- </h2>
➜what is kepler's law??

Kepler gave the three laws or theorems of motion of the orbitals bodies

This law state that the celestial bodies revolves around the stars in elliptical orbit and star as a single focus.
Example :- Earth revolves around the Sun as assuming it as single focus
This also shows that earth revolves around the sun in elliptical orbit.

Area covered by the planet is equal in equal duration of time irrespective of the position of the planet.
It also states that Angular momentum is constant
As Angular momentum is constant it means areal velocity is also constant.

where:-
A is the area.
T is the time.
L is the angular momentum.
M is the mass of the body.

square of the time of the revolution is directly proportional to the cube of the distance between the planet and star in Astronomical unit.

where:-
T = time of revolution
a is the distance between the planet and star.

True that is what a convection current is