Well a question to ask would be if the mass of the material has changed significantly as that would determine that the substance is radioactive or if there have been any high readings found by a Geiger meter in certain period of time
hope that helps
Answer:
12
Explanation:
the 4 by the element symbol O multiplied by the 3 on the outside of the parentheses
One disadvantage would be the loss of the habitat of many native species, deforestation is not good.
Answer:
The First layer is the troposphere. The troposphere is what we live in. It creates weather for us. Second layer is the Stratosphere. You will find the ozone layer in it. The ozone layer helps protect us from ultraviolet radiation (UV) from the sun. In fact, the ozone layer absorbs most of the UV radiation the sun sends to us. Life as we know it wouldn't be possible without this layer of protection. Third layer is Mesosphere. The Mesosphere is very important for earth's protection. The mesosphere burns up most meteors and asteroids before they are able to reach the earth's surface. Fourth layer is Thermosphere. The Thermosphere absorbs the sun radiation making it very hot.
Explanation: I don't know if you include this one but the fifth layer is the Exosphere. Although the exosphere is the most distance layer of earth's atmosphere it is the layer that is the planet's first line of defense against the sun's rays. It is also the first layer to come into contact and protect the earth from meteors, asteroids, and cosmic rays.