Why are carbon dioxide concentrations expected to increase? a. carbon dioxide concentrations are expected to increase, because fossil fuel burning is expected to increase. b. carbon dioxide concentrations are expected to increase, because of an increase in agriculture. c. carbon dioxide concentrations are expected to increase, because more land will have to be cleared for increasing populations and agricultural use. d. all of the above select the best answer from the choices provided a b c d

Over the past decades, the concentration of carbon dioxide in the atmosphere has increased greatly as a result of human activities. The major human activity that contributes to increase in the concentration of atmospheric carbon dioxide is the burning of fossil fuels.

Explanation:

c. earths continental crust is thicker than its lithosphere.

because, the lithosphere is the outermost layer of the earth/ 100 km thick and is defined by its machanical properties.the lithosphere contains oceanic and continental crust that varies in age and thickness across locations and geologic time. the lithosphere is the coolest layer of the earth in terms of temperature. the term lithosphere should not be confused with the use of "geosphere" which is used to indicate all of earth systems, including the atmosphere, hydrosphere   and biosphere. the surface of the earth can be divided into the continental crust and the oceanic crust.   the continental crust is made mostly of granite while the oceanic crust is made of basalt. the average thickness of the continental crust is 25 miles and the average thickness of the oceanic crust is 5 miles.   three types of rock, igneous, sedimentary, and metamorphic, make up the surface of the earth. that's why 3 option is preferable.