Tritium (³H) Is Used in Glowing "EXIT" Signs Located Where

question 123

Multiple Choice

Tritium (³H) is used in glowing "EXIT" signs located where there is no electricity for lightbulbs. If the half-life of tritium is 12.26 years, what percentage of the original quantity of the isotope is left in the sign after 18.5 years?

• A)0.632%
• B)63.2%
• C)35.1%
• D)1.51%
• E)25.0%

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Definitions:

Passive Sentences

Sentences where the subject receives the action of the verb, emphasizing the action rather than who is performing it.

Middle Adulthood

The stage of adulthood between early adulthood and late adulthood, beginning at 40 to 45 and ending at 60 to 65.

Visual Stimuli

External objects or events in the environment that are seen and can elicit a response from the visual system.

Aptitude

A natural ability to do something or to learn something, often related to skills and talents.