PLEASE HELP!

A researcher performed an analysis of the elemental composition of several fish species living in the
same body of water. The amount (in parts per million) of iron (Fe), calcium (Ca), potassium (K), sodium
(Na), and magnesium (Mg) found in each species is shown in the table.
45.10
Species Fe
Ca
K
Na
Mg
Species A 55.70 179.51 107.94 45.39
33.89
Species B 23.74 134.16 105.19
33.38
Species C 67.18 785.18 103.60 42.71
32.45
Species D 30.09 457.59 107.97 44.68
33.84
Based on this data, identify which elements are found in similar concentrations across all species of fish
tested. Explain how this data provides support for the hypothesis that all four species of fish descended
from a common ancestor.