For those of you who don't subscribe to the bimonthly print edition of Foreign Policy, you're missing a great feature: the FP Quiz. It has eight intriguing questions about how the world works.

The question I'd like to highlight this week is:

If the United States deported all its illegal immigrants at once, how long would the bus convoy be?

a) 18 miles    b) 180 miles    c) 1,800 miles

Answer after the jump ...

Answer:

C, 1,800. To deport the 12 million illegal immigrants in the United States en masse, it would take more than 200,000 buses, stretching more than 1,800 miles, according to a December 2009 Center for American Progress (CAP) report. (I did the math, and that would amount to 47.5 feet per bus and 60 people per bus. Of course, in real life, some people would have to be sent home via airplane.)

The cost would be nearly $300 billion over five years, the think tank estimates. (I did the math again, and that would be 110 buses per day at a cost of $25,000 per illegal immigrant, which presumably includes the costs of apprehension, detention, legal proceedings, and transport, based on the methodology in this 2005 CAP report, which uses older numbers.)

Arguing that this type of undertaking is unrealistic, the 2009 report says immigration reform must resolve the status of unauthorized residents; otherwise, they're receiving "amnesty by inaction."

How logistically realistic do you think mass deportation would be, given that the United States is capable of sending men to the moon?

(And for more questions about how the world works, check out the rest of the FP Quiz.)

(In the photo above, South Korean buses near the border with North Korea transport tourists from the North's Kumgang resort on July 13, 2008.)