Many countries were affected by communism after World War II. Since I can't see your map, I'll just give some examples.
Cuba- USSR supplied them with missiles to use as a defense mechanism (Cuban Missile Crisis), this was the closest the USA and the USSR came to fighting a war
Eastern European Countries- USSR took over and they became communist
The USA- Engaged in a Cold War with USSR from 1945 and until 1991
Vietnam- Vietnam War, Communists won and took control
Korea- The communists from the North tried to take over the non-communist South. They went to war and ended up splitting it in the middle (38th parallel).
If the change in values of one set doesn't affect the values of the other, then the variables are said to have "no correlation" or "zero correlation." A causal relation between two events exists if the occurrence of the first causes the other.
The Soviet Union became a democratic state.
I believe it's Slaves because they came from Africa.
