Solve the Problem $\mathrm { f } ( \mathrm { x } ) = 600 ( 0.5 ) ^ { \mathrm { x } / 80 }$

question 113

Multiple Choice

Solve the problem.
-The function $\mathrm { f } ( \mathrm { x } ) = 600 ( 0.5 ) ^ { \mathrm { x } / 80 }$ models the amount in pounds of a particular radioactive material stored in a concrete vault, where $x$ is the number of years since the material was put into the vault. Find the amount of radioactive material in the vault after 140 years. Round to the nearest whole number.

• A) 404 pounds
• B) 178 pounds
• C) 171 pounds
• D) 525 pounds

---

Definitions:

Cognitive Development

The process of growth and change in intellectual capabilities such as thinking, reasoning, and understanding, through childhood and adolescence into adulthood.

Identity Status

Refers to the four stages of identity development proposed by James Marcia, including achievement, moratorium, foreclosure, and diffusion.

Identity Achievement

A stage in identity development where an individual has explored various options and made deliberate choices, resulting in a sense of self.

Identity Moratorium

A phase in Erik Erickson's theory of psychosocial development where an individual is actively exploring and questioning various personal identities but has not yet committed to one.