In an oil drop experiment, the following charges (in arbitrary units) were found on a series of oil droplets : 2.30×10^–15, 6.90 × 10^–15, 1.38 × 10^–14, 5.75 × 10^–15, 3.45 × 10^–15, 1.96 × 10^–14. The experimental value suggests not possible magnitude of the charge on the electron is (in the same arbitrary unit)