Use the Fact That the Quantity of a Radioactive Substance

question 82

Multiple Choice

Use the fact that the quantity of a radioactive substance after t years is given by where is the original amount of radioactive material and k is its half-life (the number of years it takes for half the radioactive substance to decay) . The half-life of strontium-90 is 25 years. Find the amount of strontium-90 remaining after 9 years if Round your answer to one decimal place.

• A) 13.6 kg
• B) 72.5 kg
• C) 7.5 kg
• D) 119.4 kg
• E) 0.2 kg

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Definitions:

Jung

Carl Jung, a Swiss psychiatrist and psychoanalyst who founded analytical psychology, known for concepts such as the collective unconscious, archetypes, and psychological types.

Spiritualistic Theories

Hypotheses or beliefs that suggest a non-physical realm or spiritual dimensions can influence human behavior and life.

Freud

An Austrian neurologist and the founder of psychoanalysis, known for his theories about the unconscious mind and the development of personality.

Basic Anxiety

Basic anxiety is a term coined by psychoanalyst Karen Horney, referring to feelings of helplessness and insecurity that arise from a hostile environment.