Starting in 1908, while a professor at the University of Chicago, Millikan worked on an oil-drop experiment in which he measured the charge on a single electron. J. J. Thomson had already discovered the charge-to-mass ratio of the electron.
The answer is 9.
First convert 40 cm into metres.
40cm/100= 0.4 metres
0.4 times 9 = 3.6
"In 1897, J.J. Thomson discovered the electron by experimenting with a Crookes, or cathode ray, tube. He demonstrated that cathode rays were negatively charged. In addition, he also studied positively charged particles in neon gas."
Source:abcte.org
Stardust atoms are heavier elements, the percentage of star mass in our body is much more impressive. Most hydrogen in our body floats around in the form of water .