Kinetic energy would be the answer I <em>believe</em><span>. </span>The faster<span> a </span>particle moves<span>, </span>the<span> more kinetic </span>energy it<span> has.</span>
It is called a hypothesis.
The atomic mass would be 28.08535 amu. Multiply 27.9769 by .92297 = 25.803. Multiply 28.9765 by .046832 to get 1.357. Multiply 29.9738 by .03872 to get .925351136. Add 25.803 + 1.357 + .03872 to get 28.08535 amu