A fifth grader looked downcast, so her teacher asked. Whats the problem Carol? I hope its not homework again. Well, uh, yes, it is, replied Carol I was stupid and made my homework paper into a paper airplane. Carol, youre right, that wasnt a very bright thing to do, said the teacher, but his once Ill let your just unfold the paper and hand it in. Oh, but that wont work, said Carol, looking even sadder. You see, the plane was hijacked.