In psychology, natural concept represents events drawn from personal experience which were initially learned by someone without necessarily expressing the logic behind it. In this case, Anita doesn't give logical explanation of art despite having learned about it but since she can identify an art, this is part of natural concept. Therefore, the right answer is natural concept.
Since the triangle has equal sides it will carry onto it self at 120, since it can rotate 360 grades only and it has 3 sides so it will rotate in one third of 360 so 120
