Radioactive decay is a spontaneous process. occurs when an unstable nucleus loses energy. does not require any input of energy. all of the above

Radioactive decay occurs when an unstable nucleus loses energy

So the answer is the second choice

frequency, z, and the collision density, z, in carbon dioxide (co2), r 180 pm at 30 °c and 120 kpa

the transfer of heat by electromagnetic radiation is called thermal radiation . it is usually carried out by electromagnetic waves in an energy range just below the visible spectrum, which is the infrared range.

so the answer would be radiation.

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