Which observation did researchers make in studies on separated twins?

The scientists observed whether the environment in which each twin was raised had an influence on his personality, behavior and temperament.

Explanation:

As we know, twin brothers have many biological and physical characteristics in common, due to all the genetic load they share. However, some scientists believe that genetics also has half the responsibility for the social characteristics of these brothers, such as behavior, temperament and personality. The other half of that responsibility is held by the environment in which these twins were raised. Thus, twins raised in the same environment, will present equal personalities and behaviors.

For this reason, scientists will start several studies with separate twin brothers who were raised in different environments. They wanted to see how changing the environment would cause differences in the brothers' behavior, temperament and personality.

the components of a vector are the parts of the vectors that are to each other.

b perpendicular