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Finite and renewable resources

from the , oceans and atmosphere will one day run out. They can be processed to provide and useful materials. are those which will not run out in the foreseeable future.

One of the most important finite resources in the crust is . Crude oil is processed through and cracking to produce a wide variety of useful chemicals. Sea water is a renewable resource because there is such a large amount of it that humans will not use it all up.

Sometimes natural products can be supplemented or replaced by and products. For example, until 1910 all were obtained from such as .

However, the enabled humans to produce fertilisers from nitrogen in the air, and has allowed synthetic fertilisers to be produced. fertilisers have allowed intensive farming to become widespread, which has meant that we can produce enough food to support the growing world population

Another example of resource exploitation is copper. The graph below shows how the estimated global population has increased since 1900.

A graph showing that the world population has grown year on year since 1960.

The graph below shows how the global use of copper has changed since 1900.

Graph of copper production since 1900

There is a clear between the increase in global population and the demand for copper. Learn more about sustainable copper extraction.

Question

By what factor did the production of copper increase between 1920 and 1995?