Dr. Raheja places a rat in a small cage where it learns to press a bar to obtain a food pellet. Obviously, Dr. Raheja is using a(n) to study learning.

Operant chamber/ Skinner box

Explanation:

Operant chamber also known as Skinner box was developed by B.F skinner in 1930s. Operant chamber are used to study the animal behavior and can be used to both operant and classical conditioning.

In an operant chamber, animal free-operant behaviour is studied through animal response to a stimulus (such as light or voice) and if the reponse was corrrect the animal would be provided with reward.

In the question, Dr. Raheja is using the operant chamber for study learning. The rat would get the food (reward) by pressing a bar (correct response).

well for one plants are always the producer, so a is the answer. a wolf is more of the consumer(predator) and the deer is the prey so i know those two are out of the question. also mushrooms are fungi/fungus so a is the producer.

if you add everything up correctly you should get 69 i got this because 50 plus 19 is it