According to one widely accepted theory, the earliest Americans crossed over from Asia on 1 simple canoes

2 viking ships

4the European Land Bridge

3the Beringia Land Bridge

the first settlements began along the huang river because of the importance of the huang river in the beginning of china. it goes back to the story, “the tale of emperor yu”, which references the tale of the great flood, which was caused by the huang river and was believed to create and influence china’s making.

answer; the automatic system because it is a "gut reactor"  

answer; all of the above are correct;

answer; multidisciplinary;