Which of these is true of the Earth system?
a. Energy rarely enters or leaves the system.
b. Matter rarely enters or leaves the system.
c. Matter easily enters the system but cannot
leave the system.
d. Energy easily enters the system but cannot leave the system.

Because electrons have negligible mass, to account for the mass of the isotope, there must be 16 neutrons, 16 neutrally charged, massive, fundamental particles present in the sulfur nucleus. and thus finally, if we have the 32s2− ion, there are 18 electrons, 16 protons, and 16 neutrons.

The answer is 65.3312

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English , i don't understand spanish.