How Long Will It Take a Sample of Radioactive Substance $\mathrm { A } ( \mathrm { t } ) = 650 \mathrm { e } ^ { - 0.189 t }$

question 180

Multiple Choice

How long will it take a sample of radioactive substance to decay to half of its original amount, if it decays according to the functi $\mathrm { A } ( \mathrm { t } ) = 650 \mathrm { e } ^ { - 0.189 t }$ , where t is the time in years? Round your answer to the nearest
Hundredth year.

• A) 3.67 years
• B) 34.27 years
• C) 122.85 years
• D) 37.94 years

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Definitions:

Compound Fracture

A type of bone fracture where the broken bone pierces the skin, creating an open wound and increasing the risk of infection.

Break In Skin

An interruption in the continuity of the skin which can be due to cuts, scratches, or abrasions, potentially allowing entry for pathogens.

DXA

Dual-energy X-ray Absorptiometry, a medical imaging technique used to measure bone mineral density and assess the risk of fractures.

Bony Projection

A protrusion or bump found on a bone that serves as an attachment point for muscles or ligaments.