Explain how scientist know the oxygen level in the atmosphere has changed because of plants.

Since plants convert carbon dioxide and grow because of the carbon it helps the plants and when that happends where there are plants there is more air produced for us to breath.It can also change the climate because of the levels of air that is produced by plants is in the  atmosthphere.So they know because there is more air and because where there are plants there is more fresh air to breath.Also plants take the carbon dioxide and clean the carbon in the air causing us to breath good air.

this is a good question! i'll do some research and come back when i have the answer!

when we think of a­ncient paga­n kings, the ideas of justice and fairness probably aren't the first things to come to mind. we moderns may be more likely to imagine fickle, power-hungry despots who were ready to put someone to death on a whim. but king hammurabi, who ruled a prosperous and thriving babyloniaalmost four millennia ago, doesn't quite fit that mold. he claimed to have protect the weak from oppression, and scholars believe he fostered an atmosphere of justice and righteousness for his people.

this belief is based on an object that was discovered only a century ago. it has already earned a place alongside the rosetta stone as one of the most important artifacts of the ancient world. this stela (stone pillar) bears the inscription of the code of hammurabi, and it has shed light on the laws, culture and life in babylonia.

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