Why did the u. s and soviet union participate in angolas civil war

Ineed because i cannot find the answers anywhere

Which of the following is not part of the constitution

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.