How Long Does It Take 200

question 14

Multiple Choice

How long does it take 200.0 mCi of a radioactive sample to decay to 20.0 mCi if its half-life is 11.0 s?

• A) 25.4 s
• B) 5.36 s
• C) 36.5 s
• D) 53.6 s
• E) 73.0 s

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Definitions:

External Auditory Canal

The passage leading from the outer ear to the eardrum, transmitting sound waves to the eardrum.

Eardrum

A delicate film that divides the outer from the middle ear, moving in reaction to sound waves.

Sound Waves

Sonic oscillations transmitted through the air or other mediums, detectable upon reaching the ears of people or animals.

Carotid Canal

A passage in the temporal bone of the skull through which the internal carotid artery enters the cranial cavity to supply blood to the brain.