What was one effect of the johnson-reed act of 1924?

the ku klux klan was revived.

the red scare quietly came to an end.

immigration from eastern and southern europe all but stopped.

refugees from nations devastated by the great war came to america in large numbers.

Using mr smith and his id, identify two potential internal validity threats that might affect the a—b design. tell me how that threat might impact conclusions in the a—b design. note #1: you cannot use maturation (since i already did that one for note #2: there are some mr smith id threats that won’t have much impact in a single case design.