I think the answer is 7mm but I'm not sure.
Have a great day!
This is what I got. Hope it helps :)
Air pollution exist in two forms namely ozone and particle pollution. CFCs and smog are under the ozone form of pollution. Ozone type of pollution is mostly formed by reaction between the sunlight and the vapors that are emitted due to human activities.
There are 6 hydrogen atoms in every molecule of ethanol
Water, because electrolysis is using electricity to break the bond of water to release 2 Hydrogens and the 1 Oxygen.