which element(s) is/are found in the stars spectra below? hydrogen & helium hydrogen & calcium hydrogen only…

Brief Explanations:

To determine the elements in a star's spectra, we match the spectral - lines in the star's spectrum with the known spectral - lines of elements. Since no star spectrum is provided in the text, we assume a general knowledge - based approach. Hydrogen is a very common element in stars. If the spectrum shows lines corresponding to hydrogen and calcium, then those elements are present.

Answer:

We cannot determine the answer without seeing the actual star's spectra. If we assume based on common knowledge and the options given, we would need to analyze the spectral lines in the provided star spectrum (not shown here). But if we had to guess without the spectrum, hydrogen is very common in stars, and if calcium lines are also present, the answer could be Hydrogen & Calcium. However, without the spectrum, we cannot be certain.