What is the main point that all of these videos are trying to show?

Newton's 2nd law- F=MA

Explanation:

This may be the completely wrong answer but judging by the pictures this was the car experiment where you add different weights to the car, raise or lower the ramp, and add different parachutes to experiment with how changing mass and height can affect the distance the car goes

the word that best describes martin luther king jr.'s tone in the video is dignified

martin luther king, jr. was a social activist and baptist minister who played a key role in the american civil rights movement from the mid-1950s until his assassination in 1968. the video shows his manner and attitude having or showing a composed or serious manner that is worthy of respect so dignified is the correct answer

i think the answer would be reserve.