Answer:
The Three Mountain Task was developed by Jean Piaget and Bärbel Inhelder in the 1940s to study children's ability to coordinate spatial perspectives. In the task, a child faced a display of three model mountains while a researcher placed a doll at different viewpoints of the display.
Explanation:
To solve this problem it is necessary to apply the concepts related to thermal linear expansion. Mathematically this concept can be expressed under the Equation:

Where,
Initial Length
Thermal Expanssion constant
Change in Lenght
Our values are given as



Replacing at our equation we have,



Therefore the expantion of the bar is 0.317mm
Answer:
Ethnomethodology theory
Explanation:
Take note of the fact that we are told Kevin worries that the police will stop and question him even though he has not done anything wrong.
This statement shows us that Kevin already understood his society from past experiences, and thus he tries to avoid social interactions with particular member of his society (the police) who may be show discrimination towards him.