a year
It depends on how good you are, but getting 1-99 Dungeoneering via an experienced leach team can be as quick as a week or two.
7080-5093 = 1987
I believe the Dungeoneering skill goes up to 120. The longest time it takes to get to 99 Dungeoneering depends on your combat level, as you go deeper in Daemonheim, the monster will be more powerful. Depending on you and your team mates levels the monsters/bosses levels will change also.
7080
yes!
0.0056
590
You need 40,000 Dungeoneering tokens, so you need to get about 400,000 Dungeoneering experience. I couldn't find any reference on how much experience you typically get per hour, and I don't have enough experience myself yet.
Depends on several factors: The number of players you are dungeoneering with. The complexity level you chose. How much of the dungeon you completed. And so on.
Dungeoneering in groups seems to give more experience than alone; but it may take a while to organize a good group.
a very long time....in my point of view without someone with you dung. is really boring
It would take about 1 month or maybe longer or shorter depending on the hours you play. but once you get 80 dungeoneering and get a chaotic weapon it is very much worth it. Also once you get your first chaotic, it has been said to be 3 times quicker for your next one :P