From the Christians point of view, why were the Crusades necessary?

What specific science discipline do most social engineering attacks rely on when they are being used?

This chart shows the number of soldiers killed according to two different sources. source a is a book written by university professors. source b is from a well-known historical website. in a paragraph, explain why the data presented is different, and evaluate the reliability of each source. which should be used in a school research project, and why?

Plz me i need a good grade ! 10 government is a government system where all citizens that choose to vote have a say in their government? a: communist b: democratic c: autocratic d: theocracy