The principle of "six degrees of separation" that suggests that everyone in the world is connected to everyone else within six steps, exemplifies which concept?

social ties

Explanation:

Six degrees of separation is a concept that describes the possibility that individuals are six "social connections" or less from one another. Therefore exemplifying the concept of social ties. This term refers to the connections that exist between individuals, which are used and created when sharing information, knowledge, feelings, and experiences.

this null effect is caused by a weak manipulation and ineffective internal validity. in a scientific study, as the one dr. morimoto is trying to perfom, internal validity refers to the confidence placed in the cause-effect relationship and to how well an experiment is done and able to eliminate confounding variables.        

stewards ice box was the purchase of alaska from russia and it was called that because people thought it was not a good idea to purchase alaska