5.05 + 5 + 5.1 = 15.15cm Then you just divide it by the amount of measurements you had like this:15.15 ÷ 3 = 5.04999971cm Then you can just round it to the 3rd figure: 5.05cm < And that's the mean/average length of the bar. :) (Or the one above if you want all of the decimals too)
If we are talking about moles then the answer to that is 0.22
Electron transitions from higher to lower energy levels cause emission of energy in the form of electromagnetic waves, each with their own specific wavelength. Because the energy levels of elements are quantized, each transition has a specific energy difference. The collection of these transitions makes up the emission spectrum and each spectrum is unique to a specific element, allowing identification.
