Answer:
The stratification of Earth into its geologic layers was brought about by the formation of the Earth's iron core. The iron core was generated by a combination of radioactive decay and gravitation, which raised the temperature enough for molten iron to form.
Explanation:
<span>As humans change the way we live on the planet, the way that nitrogen moves around the Earth also changes. Nitrogen atoms may seem small enough to be easily overlooked. We look right through the ones in the air, do we not? Yet recent changes in the nitrogen cycle are causing a very noticeable effect on natural environments and human health. Lakes are clogged with aquatic weeds. Dead zones have formed in areas of the oceans where animals can not survive. Air pollutants that contain nitrogen are decreasing air quality and greenhouse gases that contain nitrogen are becoming more common.</span>
B, virtues.
A virtue is a trait or quality that is deemed to be morally good and is valued as a foundation of principle and good moral being. Personal virtues are characteristics valued as promoting collective and individual greatness.
