The two factors that are most likely to affect whether a galaxy will evolve by merging with a second galaxy are:
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Its size compared to that of the other galaxy - The gravitational interactions that lead to merging are significantly influenced by the mass (and consequently size) of the galaxies involved. Larger galaxies have a stronger gravitational pull and are more likely to result in a merger.
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Its proportion of gas compared to that of the other galaxy - The amount of gas in galaxies can influence their evolution and the likelihood of merging. Gas-rich galaxies can fuel star formation and are more likely to interact gravitationally and thus merge compared to gas-poor galaxies.
These factors play a critical role in the dynamics of galaxy interactions and potential mergers.