In pavlov's studies on classical conditioning, the bell was a(n) before it was paired with the food.

conditioned stimulus (CS)

Explanation:

This neutral stimulus is called the conditioned stimulus (CS): Its power to elicit behav- ior is conditioned on its association with the UCS. After several trials, the CS will produce a response called the conditioned response (CR).

spiders belong to a group of arachnids.

arachnids have the following traits :

they have two body parts.

they have eight legs unlike insects which have 6 legs.

they have no wings.

these traits distinguish them from insects.

the information that antonio is doubting us the statement that spiders differences are as a result of being first to evolve.

this is because the evolution of one species is independent of the other species.

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