During the roaring twenties the U. S had just got out of And business Was booming

the answer is true!                                          

i believe the answer is:   psychological  experiment

in this experiment, wilhelm wundt became the first person that implement scientific method in analyzing the pyschological phenomenon.

due to this result, wilhelm wundt also able to make psychology to be acknowledged as a separate scientific field from biology.

answer; sellers provide full and accurate information about loan terms;