In the nucleus of a cell.
<span>The biological term for such organisms is "deuterostomes". Those who's first opening is the mouth are called protostomes.
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Letter B. is the correct answer
Mark as brainleast plzzz
It's both B.They can never be depleted and C.They are replaceable by natural means.
Atoms are the basic building blocks of ordinary matter. Atoms can join together to form molecules, which in turn form most of the objects around you. Atoms are composed of particles called protons, electrons and neutrons.