You guys are ****s. A class ****s, Infact, you are worse than ****s, I just can't say it on this forum.
I would guess so, I'm not a car person, But I believe the "hub" is attached for decals, And or to hold center mass in the tire, So the lugs can evenly distribute pressure and weight.
To answer the first part of your question, nascar can get four tires changed (Two tire changers) in as little as 14.7 seconds. That's 6 lug nuts each tire, and a hub in the center.
I suppose that is Incase one pops off, You can still continue on, But the "Hub" is most likely to hold a hubcap on, But since that tire doesn't have one it's safe to say it was used as a decal.
No sir, As the picture above states, You need more lug nuts than that to keep the tire on, You wouldn't want to go 180+ MPH knowing the only thing holding you on the rubber, is 1, Big ass lugnut. That is most likely a show room car ( Those rims are not meant for racing, I don't believe ) And the weight of a car breaking =/= Under amounts of stress is quite dangerous. One lug nut could undergo serious wear and tear before the stint of the tire is complete, I would put my bets on metal fatigue. It depends on the width of tire you need to race correctly. If you need slicks, you're probably rolling with 4 to 6. If you are going with a ricer car and big ass 21'' rims you probably will have 1 - 8. The reason that can be one is if the car is only cruising, Then it wouldn't matter, Low profile tires can probably handle 1 lug nut and or hub because it's not under much stress, The rim supports and is 3/4's of the tire/rim itself. However bigger tires mean you possibly need more support for the tire. Thus is the reason race cars can go with so less.
Imagine yourself holding about 2,000 pounds, Plus occasional stopping, turning, break dust/heat. And you only have 1 friend for support. I know that sounds retarded, But you should be able to wrap your head around that, the more friends, The better.
I'm just repeating myself now, But the height/width of the tire determines the height/width of rim, the aspect ratio of both most likely determines what and how many lug nuts to use. Depending on forces expected - Weight braking / accelerating
Then again, I'm not a car person.
Edit: I should add, I forgot the fact nascar now uses 5 lug nuts, And slightly harder compounds.