Is a Relational Set Operator

question 47

Multiple Choice

is a relational set operator.

• A)MINUS
• B)PLUS
• C)ALL
• D)EXISTS

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Definitions:

Club Mosses

Prehistoric plants from the Lycopodiophyta division, identified by their club-like reproductive organs and similarity to mosses.

Horsetails

Members of the genus Equisetum, they are non-flowering plants with a hollow, jointed stem that reproduce through spores, often found in wet environments.

Carboniferous Period

A geologic period and system that spans 60 million years from the end of the Devonian Period 358.9 million years ago, to the beginning of the Permian Period, characterized by the first extensive forests of ferns and seed plants.

Protonema

A thread-like chain of cells that forms the earliest stage of a moss or fern life cycle, emerging from the spore and developing into the gametophyte.