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

question 136

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 20.0 years?

• A)0.677%
• B)67.7%
• C)32.3%
• D)0.323%
• E)25.0%

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Definitions:

Brake Pedal

A mechanism that activates the brake system in a vehicle, allowing the driver to slow down or stop the vehicle by pressing down with their foot.

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