True. The first world war was the first war in which mechanized warfare was prevalent on both sides. The advanced technologies of the powers meant that they could cause more destruction than ever before. Consequently, the causalities for WWI were the highest ever up to that point in time. <span />
A change that occurred in the US military following the end of the Vietnam War was C.) It became an all volunteer force.
Just took it on Egde
A secondary source conclusion is valid.
The role that Harriet Tubman played in during the Civil War was to work for the Union army as a nurse, cook and spy. She helped the slaves escape which was very helpful because she knew the land very well and knows which path to take when trying to avoid soldiers.
She recruited a group of former slaves to hunt for rebel camps and report on the movement of the Confederate troops.
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