Mendeleev watched that tellurium has compound properties like different components in its gathering, and he didn't realize that neutrons cause the more noteworthy nuclear mass. Mendeleev expressed that he anticipated that tellurium would have a lower nuclear mass than iodine.
Answer: D.) 39,200 J
Via the equation of potential energy PE = mgh where m is mass, g is the average gravity on earth and h is the height. In this case m = 400 kg, g = 9.8, h = 10 m thus:

P.E.= 39,200 Joules
Proton positive; electron negative; neutron no charge<span>. </span>The charge<span> on the proton and </span>electron<span> are exactly the same size but opposite. The same number of protons and </span>electrons<span> exactly cancel one another in a neutral atom.
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