How much nicotine is in a puff? How are you measuring a puff, and how are the individual users measuring a puff? My first several disposable vapes stated 300 p

How much nicotine is in a puff? How are you measuring a puff, and how are the individual users measuring a puff? My first several disposable vapes stated 300 puffs; it took me running out much faster than a pack of cigarettes to actually measure; my starting usage I got 101 puffs. How much nicotine was in each of those puffs?