There are four main groups of organic molecules<span> that combine to build cells and their parts: carbohydrates, proteins, lipids, and nucleic acids. So it would be C. Lipids</span>
Answer: Heres my Answer
Explanation: A molecule is defined as two or more atoms of the same element different element that are bound together. A molecule may be homonuclear, which means, it consists of atoms of one chemical element, as with oxygen (O2); or it may be heteronuclear, a chemical compound composed of more than one element, as with water (H2O).
N positron emission, also called positive beta decay (β+-decay), a proton in the parent nucleus decays into a neutron that remains in the daughter nucleus, and the nucleus emits a neutrino and a positron, which is a positive particle like an ordinary electron in mass but of opposite charge.
Two atoms that contain the same number of protons but different neutrons are isotopes of the same element.their masses are different but they react the same way chemically
The railroad industry used coal to power steam engines, allowing businesses to build more factories for the production of goods.
Explanation:
It is also during the 1800s that the use of coal power enabled the smelting of iron and steel, in addition to the powering of steam engines. Coal and steam engines enabled the building of railroads to transport goods from industries.
Before the discovery of coal in the 1600s, energy was sourced from water wheels and the burning of biomass.
In addition. 1950s saw coal production decline to its lowest levels because it was overtaken by petroleum as the main source of energy.
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