The correct answer is D. Becquerel showed that uranium gave off radioactivity, and the Curies discovered other radioactive elements.
Since energy cannot be created nor destroyed, the change in energy of the electron must be equal to the energy of the emitted photon.
The energy of the emitted photon is given by:

where
h is the Planck constant
f is the photon frequency
Substituting

, we find

This is the energy given to the emitted photon; it means this is also equal to the energy lost by the electron in the transition, so the variation of energy of the electron will have a negative sign (because the electron is losing energy by decaying from an excited state, with higher energy, to the ground state, with lower energy)
The inaccurate measurements must be similar to the other two measurements (ex; 590, 589, 599), but different from the actual volume of water. (Ex; the actual volume is let say.. 100, but you measured 50, 49, 40)
Answer: An electric circuit includes a device that gives energy to the charged particles constituting the current, such as a battery or a generator; devices that use current, such as lamps, electric motors, or computers; and the connecting wires or transmission lines.
Explanation: Hope this helped! <3