calculate The number of neutrons present in the nucleus if an atom X with number of electron 15, and mass number 31. identify the Element..

ans=17. Chlorine

Explanation:

You subtract 15 which is the electron from 35 which is the mass number to get the neutron, and note number of electrons is same as number of protons. chlorine is the 17th element of the periodic table

c because the action was the roller coaster reaches bottom of hill (action) reaction would be blood tends to drain away from head

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