In Positron Emission Tomography (PET),a Positron Emitted from an Unstable

question 108

Multiple Choice

In positron emission tomography (PET) ,a positron emitted from an unstable isotope travels a short distance before it is annihilated by

• A) an electron,creating a proton that is detected by the instrument.
• B) a neutron,creating two gamma rays that travel in opposite directions.
• C) an electron,creating two gamma rays that travel in opposite directions.
• D) an alpha particle,creating two protons that travel in opposite directions.
• E) gamma ray,creating an electron that is detected by the instrument.

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Definitions:

Retained Earnings

Profits that a company keeps or reinvests for expansion or debt payment, rather than distributing to shareholders as dividends.

Stock Split

A corporate action to increase the number of outstanding shares by dividing each share, which typically lowers the stock price but does not affect the company's market value.

Market Price

The contemporary market price for transactions involving an asset or service.

Stock Split

A corporate action where a company divides its existing shares into multiple shares to increase liquidity.