The Figure Above Shows the Geological Times Scale

question 77

Multiple Choice

The figure above shows the geological times scale. Animals have been present on land for approximately _ of the Earth's history.

• A)3/4
• B)1/5
• C)1/2
• D)1/10

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Definitions:

pH

Measure of the number of hydrogen ions in a water-based fluid.

Surface Tension

The elastic tendency of a fluid's surface that allows it to resist an external force, due to intermolecular forces.

Solvent

Liquid in which other substances dissolve.

Cohesion

The force that holds molecules of the same substance together, such as water molecules in a drop of water.