In this example, john's whistling is serving as a discriminative stimulus.
This procedure, studied by Ivan Pavlov, shows a stimulus ( in this case the action of John's whistling) and a response ( the cattle run to the food trough).
Pavlov studied it with dogs. He realised that when a trainer fed them, dogs salivated. So, he presented the dogs with a "stimulus" ( the sound of a metronome) and when he gave the dogs food. After a few repetitions, when the dog listened to the stimulus, it salivated.
Four scourge and seven years ago. it marks the day that we got independence from great britain which lincoln recited in his speech due to slavery at the time
Answer:
Social referencing.
Explanation:
While acquiring new knowledge of environmental events, infants are able to regulate their attitudes towards people and objects in compliance with the affective display of their caregivers. Social referencing refers to the observation of facial expression by children to understand the situation, persons and the environment around them.
If the Confederacy had been a separate nation, it would have ranked as the fourth richest in the world at the start of the Civil War. The slave economy had been very good to American prosperity. By the start of the war, the South was producing 75 percent of the world’s cotton and creating more millionaires per capita in the Mississippi River valley than anywhere in the nation. Slaves represented Southern planters’ most significant investment—and the bulk of their wealth
