By Middle Cretaceous, __________ Became the Primary Builder of Low

question 24

Multiple Choice

By Middle Cretaceous, __________ became the primary builder of low organic banks on the shallow seafloor.

• A) neogastropoda
• B) rudists
• C) hexacorals
• D) cheilostomes

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Definitions:

Depth of Field

In photography and optics, the distance between the nearest and the furthest objects that are in acceptably sharp focus.

Total Magnification

The enlargement level of an image as seen through a microscope, calculated by multiplying the objective lens magnification by the eyepiece lens magnification.

Cross-Sectional Area

The total area within the boundary of a three-dimensional object when it is cut through perpendicularly to its longest axis.

Field Diameter

The length of the visible field observed through the microscope or another imaging device.