Answer:
Inventions like the airplane and machine gun
Explanation:
World War I was so deadly because all of the new weapons that were invented. New technology that was being invented such as machine guns and mustard gas made war deadlier than every war before.
The students who marched at Selma were better prepared in a
sense that unlike their adult counterparts, they were already briefed on what
to expect when this march began. Youth
was also their biggest asset as they were energized and determined to promote the
civil rights movement in the South. Even before the march, they were already
veterans of other movements for equal rights.