The gravitational energy is going up subtracting the energy that was on the ground
The most probable reason why the magnets won't stick on the refrigerator is that the body of the refrigerator and the magnets have like poles. If both have negative or both have positive poles facing each other, they will repel. In principle, magnets are attracted to opposite poles and like poles repel.
<span>rocky surface
(outer plants are made of gas)</span>
RT = R1 R2/ R1 + R2
R1 = R2 = 2k ohm
RT = R/2 = 2k/2 = 1k ohm