Fluorine-18 Undergoes Positron Emission with a Half-Life of 1

question 115

Multiple Choice

Fluorine-18 undergoes positron emission with a half-life of 1.10 × 10² minutes. If a patient is given a 248 mg dose for a PET scan, how long will it take for the amount of fluorine-18 to drop to 83 mg? (Assume that none of the fluorine is excreted from the body.)

• A) 99 minutes
• B) 1.7 × 10² minutes
• C) 1.3 × 10² minutes
• D) 3.0 × 10² minutes
• E) 2.1 × 10² minutes

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Definitions:

Inelastic

Refers to a situation where the demand or supply for a good or service is not significantly altered by changes in price.

Concerts

Public performances of music by artists in front of an audience.

Relative Change

A metric that measures how much a particular quantity has changed over time relative to the initial amount.

Inelastic

A characteristic of a good or service whose demand or supply is relatively unresponsive to changes in price.