10 Billion dollars, or whatever, is only an impossible goal because you believe it to be that way. You make your own limits and law of attraction answers that by making it true. Warren Buffet went from being worth 6000 USD to over 67 Billion USD. He didn't follow deliberate creating like we do on this loa forum, but a lot of his thought patterns were the same in that he had his goals, and he had no limiting beliefs stopping him reaching those goals.
Ending world poverty: well the knowledge is there already and so are the resources and the technology. If we focus on war, there will be more war. If we focus on poverty, there will be more poverty. Law of Attraction manifests what we focus on. We need to shift our attention instead to abundance for all. It is definitely not an impossible dream, and I think that if we all use our collective consciousness and picture a world where everyone has their needs taken care of, then there is a good chance of that goal being reached even in our lifetimes.
With the job competition, again if you focus on the large number of people going for the job, you are immediately etching deep into your subconscious mind that this is a difficult or impossible goal - and you will fulfill that prophecy by not getting the job.