A Radiograph of a Parietoacanthial (Waters Method) Projection Reveals That

question 24

Multiple Choice

A radiograph of a parietoacanthial (Waters method) projection reveals that the petrous ridges are superimposed over the lower 30% of the maxillary sinuses.What specific positioning error (if any) led to this radiographic finding?

• A)Insufficient extension of skull and neck
• B)Excessive extension of skull and neck
• C)Excessive CR angulation
• D)No error exists; accept the initial radiograph.

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Definitions:

Average Total Cost

The average total cost is the total cost of production divided by the quantity of output produced.

Marginal Cost Curve

A visual diagram that illustrates the variation in the cost to produce an additional unit of a product as the quantity produced changes.

Average Total Cost Curve

A curve that shows the average cost per unit of output at different levels of production; it typically has a U-shape.

Marginal Cost

The climb in cost associated with generating another unit of a product or service.