Earth's Magnetic Field

question 13

Multiple Choice

Earth's magnetic field

• A) is variable, and it has phased to zero some nine times during the past 4 million years.
• B) is constant in its intensity.
• C) remains a mystery as to its cause.
• D) is principally generated in the inner core.

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Definitions:

Neurotransmitter

Chemical substances that transmit signals across a synapse from one neuron to another neuron, muscle cell, or gland cell.

Maternal Employment

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School Phobia

An extreme fear or anxiety related to attending school, often resulting in refusal to go to school and adverse emotional responses.

Monozygotic

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