The First Animals with Simple Nerve Nets Probably Evolved About

question 83

Multiple Choice

 The first animals with simple nerve nets probably evolved about _________ years ago.

• A) 4.5 billion
• B) 3.5 billion
• C) 700 million
• D) 250 million

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Definitions:

Coefficient of Determination

A statistical measure, often denoted as R-squared, that represents the proportion of the variance in the dependent variable that is predictable from the independent variable(s).

Independent Variable

A variable in an experiment or analysis that is manipulated or categorized to observe its effect on a dependent variable.

Dependent Variable

The variable in an experiment that is expected to change as a result of manipulations of the independent variable.

Hydroxide ions

Negatively charged ions made up of one oxygen and one hydrogen atom, symbolized as OH-.