A good book to memorize 100 questions ?
Well, American History from day 0 till now and Advance Geography.
Also many books on WW1 and WW2 + documentaries. This would take a normal person a few years to really know all the reasons behind the events and all the connections.
For US National Holidays I recommend movies, shows, YouTube.
For the names in politics i recommend a lot of TV, about 6 to 8 ours per day.