What happened to the climate around 4000 BCE

Sea Level Changes late Holocene sea level ( BC) Holocene delta development worldwide (3500 BC) By 4000 BC sea level rise began to slow and deltas begin to form. ... A notable example is the mesopotamia delta (3200 BC) in times leading up to the great flood. This is a condition that had not existed for 120,000 years

Source : Book

answer:

d. because dr. laguardia selected a widely used measure, his study generalizes to has strong external validity. external validity has limited external validity. other applications of this measure.

the widely used measure that he applied to his experiment was the benton facial recognition test. it employed on to football players and as result, only players who suffered brain concussions did not pas this test. and although it has an external validity, it is limited because it isn't general to apply to other population.

the old way of life was represented by superstition, an angry god, and absolute submission to authority. the thinkers of the age of reason ushered in a new way of thinking. this new way championed the accomplishments of humankind. individuals did not have to accept despair. science and reason could bring happiness and progress. kings did not rule by divine right. they had an obligation to their subjects. europeans pondered the implications for nearly a century. americans put them into practice first.