The figure below shows the spectra of 4 objects in the sky (…
The figure below shows the spectra of 4 objects in the sky (the short wavelengths of the spectrum are on the left and the long wavelengths on the right of the spectra). One object is at rest (does not move with respect to the observer), whereas all the others are moving away from the observer. Complete the sentence: The object at rest is …, and the one moving away with the highest speed is …