How important are are the use of sources in studying a history

Using sources are extremely important because we weren't alive at the time, so we won't know what happened unless we get our information from somewhere. Sources can include maps, writing, pictures, documents, or even a person if they were alive at the time, or they got there information from other sources.

lend lease program was passed by congress on march 11, 1941. the president could ship weapons, food, or stuff to any country whose struggle against the axis assisted u.s. defense