Figuring out how to come up with enough money to retire is tough enough. Making it even harder is the uncertainty over what to expect now and in the future: What will your investments earn, how long will you be able to work, can you count on pulling money from your home down the road? To plan better, test yourself. Take our quiz to see if you know what the experts are saying about those unknowns. Ace the quiz? Share your score on Facebook or Twitter. Not so good? See what you can do to raise your game.