When setting up wireless encryption, what works like a password?

Show that the set difference metric given by d(A, B) = size(A ? B) + size(B ? A) satisfies the metric axioms given on page 70. A and B are sets and A ? B is the set difference.

Use ____ to record ideas, spur-of-the-moment questions, and even words that you would like to recall or use at a later time.

A. notes B. journals C. cards D. shortcuts