In December 1, the U.S. Citizenship and Immigration Services department will

launch a new citizenship test for greencard holders who qualify to become U.S. citizens.

This is a multiple choice test consisting of 20 questions. Assume that the rst ve

questions relate to the principles of American government, and that each of these

questions has four options of which only one option corresponds to a correct answer.

If someone guesses at random on each of the American government questions, what is

the probability that they will get exactly 2 answers correct?