A Patient Is Injected with a 5

question 88

Multiple Choice

A patient is injected with a 5.0 M solution of gallium citrate containing radioactive gallium-68 for a PET study. The half-life of gallium-68 is 9.4 hr. How long does it take for the activity of this isotope to drop to 1% of its initial value?

• A)18 hr
• B)25 hr
• C)32 hr
• D)41 hr
• E)62 hr

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Definitions:

Psychology

The science that studies behavior and mental processes.

Behavior

Actions or reactions of an organism, often in response to external stimuli, observed and measurable.

Introspection

The examination of one's own conscious thoughts and feelings, used in psychology as a method of exploring the workings of the mind.

Wilhelm Wundt

Wilhelm Wundt, often considered the father of modern psychology, founded the first psychological laboratory in Leipzig, Germany, marking the formal beginning of psychology as an experimental and scientific discipline.