A fifth grader looked downcast, so her teacher asked

A fifth grader looked downcast, so her teacher asked, "What's theproblem, Carol? I hope it's not homework again.""Well, uh, yes, it is." replied Carol. "I was stupid and made myhomework paper into a paper airplane.""Carol, you're right, that wasn't a very bright thing to do," said theteacher, "but this once I'll let you just unfold the paper and hand itin.""Oh, but that won't work," said Carol, looking even sadder. "You see,the plane was hijacked."