The charge on any negatively charged oil droplet is always a whole-number multiple of the fundamental charge of a single electron. If Millikan was measuring the charge on an oil droplet with 6 negatively charged electrons on it, what charge would he have measured on the droplet

it is called kinetic energy

the skeletons of most mammals reach a certain size and then stop growing. however, many animals, including some mammals, keep growing throughout their lives. kangaroos, for example, just keep growing and growing until they die. also, the longer an animal lives the greater the chance it might catch some deadly disease.