The Following Questions Refer to the Description and Figure Below

question 66

Multiple Choice

The following questions refer to the description and figure below.
The figure represents a cross section of the sea floor through a mid-ocean rift valley, with alternating patches of black and white indicating sea floor with reversed magnetic polarities. At the arrow labeled "I" (the rift valley) , the igneous rock of the sea floor is so young that it can be accurately dated using carbon-14 dating. At the arrow labeled "III," however, the igneous rock is about 1 million years old, and potassium-40 dating is typically used to date such rocks. Note: The horizontal arrows indicate the direction of sea-floor spreading, away from the rift valley.

Figure 25.1
-Assuming that the rate of sea-floor spreading was constant during the 1-million-year period depicted above, Earth's magnetic field has undergone reversal at an average rate of once every

• A) 10,000 years.
• B) 25,000 years.
• C) 100,000 years.
• D) 250,000 years.
• E) 1,000,000 years.

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Definitions:

COPD

Chronic Obstructive Pulmonary Disease (COPD) is a chronic inflammatory lung disease causing obstructed airflow from the lungs, symptoms include breathing difficulty, cough, and wheezing.

Bronchitis

an inflammation of the bronchial tubes in the lungs, often resulting in coughing, difficulty breathing, and mucus production.

Emphysema

Disorder of the respiratory system, specifically the lungs, that is characterized by damage to the alveoli, thus reducing the ability to exchange gases with the external environment.

Mycobacterium

A genus of bacteria known for causing diseases such as tuberculosis and leprosy in humans.