Answer:

Explanation:
The energy difference between the energy levels involved in the transition of the electron is directly proportional to the frequency of the emitted photon:

Where h is the Planck constant. The photon's frequency is inversely proportional to its wavelegth:

Here c is the speed of light. Replacing (2) in (1):

Answer:
because it is from a mathematical combination of SI base units
Explanation:
6. D
7. D
8. B
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The kinetic energy (KE) is 250 J and the gravitational potential energy (GPE) is 392 J