The Principia Mathematica was written by Alfred North Whitehead
The answer is going to be D. Around the 1980s, women had a higher percentage of college degrees.
What caused industrial psychologists to begin working with the military was <span>U.S. entry into WWI.
After years of upholding its isolationist policy of not getting involved with any wars it has nothing to do with, the US actually decided to go back on that decision and join the WWI. This is why many psychologists started working with the army in order to help the soldiers.
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Explanation:
appeasement, the Great Depression, Hitler and the Nazis, Japanese Expansion, Fascism.
