What percent of water used for farming is groundwater? How much iron is in the Earth's crust? What is groundwater modeling? How deep is the lithosphere? How much copper is in the Earth's crust? What is the relationship between groundwater and aquifers?
About 50 percent of the species on Earth became extinct, including many other large reptiles, like pterosaurs and plesiosaurus, as well as lots of plant species and marine animals. Other life forms, such as ferns, flourished by taking advantage of the sudden abundance of natural resources. ...
Tropical forests cover about three percent of the Earth's land, about 177 billion hectares of the planet's land. The world's largest tropical forest...Become a member and unlock all Study Answers Start today. Try it now Create an account Ask a question Our experts can answer your ...
They spend about 1,700,000,000 pounds on cards every year. However, the number of people sending cards and letters is falling. More than 30 percent of UK children have never sent or received a handwritten letter. Should the tradition...
How much water is on Earth?30 related questions found Is 70 of Earth's water? About 71 percent of the Earth's surface is water-covered, and the oceans hold about 96.5 percent of all Earth's water. Water also exists in the air as water vapor, in rivers and lakes, in icecaps and...
Like other species, we are the products of millions of years of adaptation. Now we're taking matters into our own hands.
Mitigation is relatively straightforward for both upstream and downstream players. Securing semiconductor plants in southeast Asia against hazards, for example, might add a mere 2 percent to building costs. Downstream players in both the rare-earth and semiconductor pipelines could mitigate impacts by ho...
East Africa is now ground zero for much of the poaching. In June the Tanzanian government announced that the country has lost 60 percent of its elephants in the past five years, down from 110,000 to fewer than 44,000. During the same period, neighboring Mozambique is reported to have los...
Mass is the measure of the amount of matter in any object. On Earth, we can weigh things to determine mass. But in outer space, something might have a lot of mass but not much weight because the pull of gravity would be small. Lots More Information Related HowStuffWorks Articles How do...
Earth is a watery place, with around 70 percent of its surface covered in water, the vast majority of which is salt water. This leaves around 30 percent of the planet's surface as potential farmland, totaling just over 57 million square miles. That's a lot of land, but much of it is...