Carbon dioxide is emitted as a by-product of clinker production an intermediate product in cement manufacture, in which calcium carbonate (CaCO3) is calcinated and converted to lime (CaO), the primary component of cement. CO2 is also emitted during cement production by fossil fuel combustion.
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Alternating sugar and phosphate molecules also 4 types of nitrogen bases
Using things such as the internet. For example, if a scientist wanted feedback, he could turn to an org of other scientists across the globe and get their help.