The correct answer is dynamo theory. The theory that explains the source of Earth's magnetic field is the dynamo theory. This theory proposes the mechanism of a celestial body such as Earth to generate magnetic field.
Answer: -70 mV
Explanation:
Assume a physiologist has inserted a microelectrode into a neuron when it is at rest. The voltage recorded at the arrow tip will be <u>-70 mV</u>.
