In millikan's experiment, the charge on each drop of oil was measured in coulombs. imagine the same experiment, but with charges measured in a fictitious unit called a zeet (z). drop charge (z) a 2.16×10−14 b 4.32×10−14 c 4.86×10−14 d 5.40×10−14 e 7.56×10−14 what is the charge on an electron in zeets

Do determine the charge of an electron in zeets, we need to find the greatest common factor among the 5 measured charges and their differences. We can do this by subtracting each of the values from the previous value and recording the differences:
4.32x10^-14 - 2.16x10^-14 = 2.16x10^-14
4.86x10^-14 - 4.32x10^-14 = 0.54x10^-14
5.40x10^-14 - 4.86x10^-14 = 0.54x10^-14
7.56x10^-14 - 5.49x10^-14 = 2.17x10^-14
Then checking for the common factor, the greatest possible one is 0.54x10^-14. So we can hypothesize that 0.54 x 10^-14 zeets (or more appropriately in scientific notation, 5.4 x 10^-15 zeets) is the charge of an electron.