<span>c. an aging population that the government must support</span>
Answer: B. Metamorphic rocks
Explanation: Metamorphic rocks are those that have undergone changes due to extreme heat and pressure. Thus, the rock, from which it becomes a metamorphic rock, is heated at temperatures above 150-200 ° and exposed to a pressure of 1500 bar. In this way, the structure of the rock is changed, in terms of the arrangement of the atoms, and the result is a change of physical and chemical properties. There are two basic types of metamorphic rocks: foliated and slate. Generally, some of the metamorphic rocks are anthracite, schist, quartzite, marble, etc.
Answer: A. Air bubbles trapped in a layer indicate how much CO2 was in the atmosphere the year the layer formed.
Explanation:
When ice cores were formed, they included air bubbles that got stuck during the formation. Scientists can study these air bubbles to find out how much carbon dioxide is in them as this will show the proportion of carbon dioxide in air at the time the core was formed.
They can then compare those figures to current carbon dioxide levels to see if there has been a change. This change will give proof of climate change.
Answer:
The greenhouse effect is a natural process that warms the Earth's surface.
Explanation:
When the Sun's energy reaches the Earth's atmosphere, some of it is reflected back to space and the rest is absorbed and re-radiated by greenhouse gases. Greenhouse gases are absorbed energy that warms the atmosphere and the surface of the Earth.