The Initial Activity of an Iridium-192 Sample Was 3000 Dpm

question 148

Multiple Choice

The initial activity of an iridium-192 sample was 3000 dpm and dropped to 375 dpm after 222 days.What is the half-life of this radionuclide?

• A)55.5 days
• B)74.0 days
• C)111 days
• D)444 days
• E)666 days

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Definitions:

Antigen A

A specific molecular structure that the immune system can identify and respond to, often associated with pathogens.

Anti-A Antibodies

Proteins in the blood that specifically target and bind to antigens with the A blood group, leading to blood cell agglutination.

Transfusion Reaction

An adverse immune response that occurs when the recipient's immune system attacks transfused blood products that are not compatible.

Anti-B Antibodies

Immunoglobulins present in the plasma of individuals with blood type A, which act against B antigens on red blood cells.