Answer
$$.^{14}N^{+}\lt .^{12}C^{+} \lt .^{14}N^{2+} \lt .^{12}C^{2+}$$
Work Step by Step
$.^{12}C^+$ has a positive 1 charge and has a mass of 12. Remember, charge is dictated by the electrons which do not have much mass compared to protons and neutrons. This has a ratio of $1/12 \approx 0.0833
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$.^{12}C^{2+}$ This has a plus 2 charge and has mass 12. Ratio = $2/12\approx .17$
$.^{14}N^{2+}$ Has plus 2 charge and mass 14. Ratio = $2/14 \approx .143$
$.^{14}N^{+}$ Has plus 1 charge and mass 14. Ratio = $1/14 \approx .07$
