From about 1000 - 1400 CE, the Pueblo people c.<span> constructed advanced irrigation systems. This was during the 300-year drought called the Great Drought. Because of this, farmers were able to develop several farming techniques to lessen their use of water in agriculture. One of the developments were irrigation systems.</span>
The one that was a factor in the U.S entry in world war I was :
B. the sinking of the Lusitania
We (as in 2016) cannot use the land bridge because of the melting of the glaciers. Back then the glaciers were still in one piece and the sea levels were much lower than now. This allowed the early people to cross the bearing straight.
<span>D. in reason. Romantics believed the truth of the world was found in emotion or feelilngs not sciene and reason. Romanticism reacted to the cold, logical way of thinking found in the Englightenment. Romantics sought feeling through religion, meditation, and experiences in life. Nature offered answers and truth and they believed it was in nature that real learning took place. </span>
They found whatever way they could