Answer:
A neutral stimulus and a stimulus that naturally elicits a response.
Explanation:
To produce a learned response in classical conditioning, the two elements repeatedly paired are the neutral stimulus and the stimulus that naturally elicits a response.
Answer:
Columbian Exchange
Explanation:
The Columbian Exchange refers to the period where there was a widespread transfer of plants, animals and culture between the Americas and Europe.
This exchange was named because of Christopher Columbus who was the Spaniard who first arrived to the Americas (while trying to find a new route from Spain to India) and started the maritime route from Europe to the Americans, starting a process of exchange of plants and animals among other things.
This exchange took place mainly during the 15th and 16th centuries.
