On May 26, 1924, the U.S. government enacted the eugenics-inspired Immigration Act of 1924, which completely prohibited immigration from Asia. The law reflected the desire of Americans to isolate themselves from the world after fighting World War I in Europe, which exacerbated growing fears of the spread of communist ideas. It also reflected the pervasiveness of racial discrimination in American society at the time.
Explanation:
Germany's condition of reduction of population is because of pandemic effect on global recolation.
Positive:There would not be much pandemics, diseases,& so on.
Negative: There would be an effect on economy, there'll be few or less workers,so on.(This would be a larger effect than the positives of course)
One reason of undergrowth is of jobless rate & bare utilisation anticipation.

I think this is the answer.
Canada, Mexico, and the United States
According to National Geographic, the maximum displacement along the fault between the two tectonic plates during the magnitude 9 earthquake in Japan was 164 feet (50 meters).
Hope it helps!