Explain why a variety of instruments are needed to measure change in the climate system

A variety is used to measure the change in the climate system because there is so much that is incorporated with the climate, that not one tool would be able to be used. There are many tools to measure different parts of the climate system, so that way a more accurate reading could be made. For example, we can say that the climate is warming up, because based off of the results, of rain, snow, and the temperature. If it was simply the temperature, then we wouldn't get any results, just that its a little warmer than last year.

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what are the choices?

the phenomenon that would be cited as evidence of increased economic interdependence between europe and the americas is  the development of mercantilism.

this theory suggests that the wealth of a country depends on its economic assets, or capital.

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