Former crack cocaine users often feel a drug craving when they are again in places they associate with previous highs. their reactions are best explained in terms of

Their reactions are best explained in terms of "Classical Conditioning".

Classical conditioning is a learning procedure that happens when two stimuli are more than once matched: a reaction which is at first inspired by the second boost is in the end evoked by the primary stimuli alone. It is important to know that classical conditioning includes automatic or reflexive responses, and not intentional conduct.

The correct selection of choices to answer to the question: The force of gravity:___, would be:

1. Changes slightly with location on the Earth

2. Decreases with height above sea level

Explanation:

Gravity is given by the attractive force that exerts the Earth on other bodies. Usually, we think of gravity as a constant, and in general, we would be right, but the truth is that gravity will be affected by certain factors, particularly on how much force it can exert on a specific object, or body. Thus, the further a body goes away from the center of gravity, the lesser that gravity exerts its power over it. However, the force of gravity will always be present, unless the body distances itself by quite a few million years from the Earth. In essence, gravity will change with location, because the force will decrease as the body gets away from the center of the force and also it will decrease with height above see level, as we ascend away from the very center of Earth, where the strongest force lies.