A research assistant in a lab conditions dogs to salivate to the sound of a bell. During conditioning, the assistant deliberately manipulates the interval between the sound of the bell and the presentation of food. After conditioning, he measures how much the dog salivates when the bell is presented alone. The interval is the variable. The amount of salivation is the variable.

What extraordinary role does learning think we can play in the universe?

In a study, people were asked to imagine simple occasions that made them happy and to remember events that made them feel proud about themselves. it was observed that the subjects developed an increasingly positive attitude. these changes are known to be healthy, leading to greater physical activity and reducing unhealthy habits. based on this excerpt, we can conclude that a positive attitude .

Under the us constitution, some powers belong to the states. choose the power that belongs to the states.