Your 3 seems kinda lowMore or less the average word per tweet plus the theoretical "hot" air coming out at which rate it would take to make about 1 ml or water to reach 100C.
A morbid question....
How many nuclear ICBMs would it take to "nuke" the entire world. (Assume you're using UGM-133A Trident II D-5 W88/Mk5 missiles and blasting every single square cm of the world )
Uh my solution to the cofveve assuming the same thing and water at room temp. Takes around 2.5E3 joules of energy for water to reach 100 degrees C and boil. One breathe is 500 ml, you can say cofveve around 10 times before breathing again so 50 ml. 50 ml weighs around 5E-5 kg. Specific heat of air is around 1 kj/kg (?) So 5E-2 joules in a cofveve. 2.5E3/5E-2 is 5E4. I'll round up because assuming normal breathing you probably would say cofveve less times so 5?
When doing Fermi questions here it'll be nice if you can explain the step by step process of how to obtain your answer so others can understand. Just saying a answer doesn't really do anything.