The Following Questions Refer to the Description and Figure 23

question 34

Multiple Choice

The following questions refer to the description and Figure 23.1.
Figure 23.1 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 23.1
-How many other bands of sea-floor crust in Figure 23.1 have the same magnetic polarity as the crust that directly straddles the rift valley?

• A) 2 bands
• B) 4 bands
• C) 6 bands
• D) 8 bands
• E) 10 bands

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Definitions:

Health Expectancies

Statistical measures predicting the average period that a person may expect to live in a specific health state, such as without chronic disease.

Health Psychology

A branch of psychology that focuses on how biological, psychological, and social factors influence health, illness, and healthcare.

Healthy People 2020

A set of goals and objectives aimed at promoting health and preventing disease for American citizens by the year 2020, focusing on various health metrics and public health interventions.

Healthy Life Expectancy

The number of years a person can expect to live in good health, taking into account years lived in less than full health due to disease and/or injury.