Is a frisbee flying through the air mechanical energy

In the millikan oil drop experiment they determined that every drop had a charge which was a while number multiple of -1.60x10^-19. if a drop has a total charge of -9.60x10^-19 then how many excess electrons are contained within the drop?

650.j is the same amount of energy as? 2720cal1550cal650.cal2.72cal

How many moles are in 43.9 l of oxygen