What Is the Average Central-Ray Angulation for the PA Axial

question 3

Multiple Choice

What is the average central-ray angulation for the PA axial (Haas) projection of the skull?

• A) 25 degrees caudad
• B) 25 degrees cephalad
• C) 30 degrees caudad
• D) 30 degrees cephalad

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Definitions:

IUPAC

The International Union of Pure and Applied Chemistry, an organization that sets standards for naming chemical compounds and elements, among other activities in the chemistry field.

Hydrogen Bonded

Describes a type of chemical bond that occurs when a hydrogen atom, which is covalently bonded to a highly electronegative atom, forms an electrostatic or partial covalent bond with another electronegative atom.

Tertiary Amides

Amides derived from carboxylic acids where the nitrogen atom is bonded to three other carbon atoms, not including the carbonyl carbon.

Secondary Amides

Organic compounds characterized by a carbonyl group (C=O) attached to a nitrogen atom, which in turn is bonded to two alkyl or aryl groups.