I didn't label the first 'Part 1', because, who knew?
Let's get down to the important physics of covid, which will never be done. The first is oxygen resistance. The covid virus is a fragile thing, one molecule of O2 will kill it, or equivalent. Think of O2 as a giant meteorite, smashing into those fuzzy hairs. BLAM! All viruses are like that, but some invest in more shielding so they can last a bit longer.
So, a single virus in the air is instantly dead. But the virus lives by being in gobs of snot. O2 takes a long time to penetrate snot, it usually requires the snot to dry. Now, it is simple physics that the large the gob, the longer the virus stays dangerous.
So, we can construct a half-life chart of particle size and viability. It would be the same in the air or on a surface. But the spectrum of particle size has a relation with ballistics and air resistance. A large gob quickly settles to the ground where you grind it up like a cockroach. Smaller ones take longer to settle.
So, you have to convolute the half-life and settlement rate. But now, we add velocity, which is simple ballistics. Most important is the muzzle velocity. Loudmouth glad-handers have a certain velocity profile, as well as panting spin-bikers.
Add the efficiency of masks. They are horrible. At Costco everybody shouts through the mask because nobody can hear them. A standard surgical mask is designed for one thing only - a nice quiet surgery.
We must then add the spectrum of what people are wearing. Blah, it goes on and on, but give me a million bucks and it can be done. (Not really, I hate to work).
It boils down to the fact that in social situations, nobody wears a mask, so that the whole room is susceptible to one loudmouth. For masks to be effective, you need official masks, and everybody wears one in the room. Happens only in China, you need 100% compliance. Maybe in Italy, where everybody died. 99% is equivalent to zero, but we allow this.
We can do more fun physics, but we need money. Any money has to come from the power structure that stands to lose their power. Human nature -- nope. This all reads the same as ozone and carbon.
It boils down to the fact that at an Indian wedding we give out safety glasses. Everybody has fun. No superspreader event, caused by one superspreader, but we can't say that because it would make them feel bad. Far better to kill everybody, rather than offend. :)