Which Element Listed Below Is Not Classified as a Lanthanide

question 21

Multiple Choice

Which element listed below is not classified as a lanthanide or actinide?

• A) Ce
• B) Sm
• C) U
• D) Fr
• E) all are lanthanides or actinides

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Definitions:

Generalization Gradient

A measure of the degree to which a conditioned response is elicited by stimuli that resemble the original conditioned stimulus.

Color-blind Monkeys

Primates that lack the ability to distinguish certain colors, used in research to understand color vision and perception.

Concurrent Discrimination

A type of discrimination training in which two or more stimuli are presented at the same time, and the correct response depends on distinguishing between these stimuli.

Two-choice Discrimination

A test situation in which an organism is presented with two different stimuli and rewarded for choosing the correct one, used to assess decision-making.