Is this a personal question or a school question?
Answer:
Beginning with the top-most layer (most recent) is necessary so as not to disturb or destroy fragile remains and the only real method. One couldn't start at the bottom and work their way up!
Explanation:
<span>The voting age was decreased from 21 to 18 because it was thought this would lead to less protesting by students. Before the age was lowered, there were young men being drafted, but they were not old enough to vote.</span>
<span>B) lincoln's election in 1860</span>
Ancient Greece only had few materials because they were surrounded by water and other countries had the goodies