Marble A moved first, and marble B moved last, thats why marble A moved farther, sorry if im wrong
The atomic number of an isotope is the number of protons it contains, whereas the mass number is the total mass of the nucleus, which is the combined number of protons and neutrons in the nucleus. To find the number of neutrons, you must therefore subtract the atomic number of the isotope from the mass number of the isotope.
<span>In the above example, the atomic number is 8 and the mass number is 18. This isotope is known as O18. The number of neutrons in the isotope is: Mass number - Atomic number = Number of neutrons
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Answer:
It would be a because it helps with immunity
<span>The endosymbiotic theory deals with the origins of mitochondria and chloroplasts, two eukaryotic organelles that have bacteria characteristics. Mitochondria and chloroplasts are believed to have developed from symbiotic bacteria, specifically alpha-proteobacteria and cyanobacteria, respectively.</span>
