How Is a Fossil Cast or Mould Formed

question 33

Multiple Choice

How is a fossil cast or mould formed?

• A) Silica fills in all open spaces in the original organic structure.
• B) Soft mud surrounds a broken dinosaur bone and hardens to a mudstone cast.
• C) An impression of the organism is formed by a thin film of carbon.
• D) A mineral such as quartz , calcite, pyrite, or apatite is precipitated in the space left by dissolution of an original shell or other hard part.

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Definitions:

Homogeneous Oligopolist

A firm in a market structure where only a few sellers offer products or services that are essentially identical, leading to limited competition.

Highly Concentrated Industry

An industry dominated by a small number of firms, leading to reduced competition and potentially higher prices for consumers.

Pittsburgh Plate Glass

Pittsburgh Plate Glass, known today as PPG Industries, is an American global supplier of paints, coatings, optical products, specialty materials, chemicals, glass, and fiberglass.

Differentiated Oligopoly

A market structure in which a few firms dominate the market, and each firm offers a product or service that is slightly different from that of its competitors.