Solve the Problem $2 \%$ Per 100 Years $t$ Represents Time in Years and Y Represents the Amount of Rate

question 63

Multiple Choice

Solve the problem.
-A certain radioactive isotope decays at a rate of $2 \%$ per 100 years. If $t$ represents time in years and y represents the amount of the isotope left then the equation for the situation is $y = y 0 e ^ { - 0.0002 t }$ . In how many years will there be $89 \%$ of the isotope left?

• A) 550 years
• B) 583 years
• C) 1100 years
• D) 244 years

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Definitions:

Egocentric Speech

Speech used by children, in which they talk about themselves and their perspective, often without regard for the listener's understanding or viewpoint.

Fast Mapping

The process in which new words are associated with their meaning after only a brief encounter.

Private Speech

Spoken language that is not intended for others, commonly used by children during the preschool years.

Scaffolded Speech

An instructional technique where the support is gradually removed as the learner becomes more proficient, often seen in language learning where a teacher or caregiver provides tailored support to match the learner's current level.