Teacher decides to let students out early if they can name some quote origins. Teacher: "Who said 'Four Score and Seven Years Ago'?" Before Johnny can open his mouth, Susie says, "Abraham Lincoln." "That's right Susie, you can go home." Teacher: "Who said 'I Have a Dream'?" Before Johnny can open his mouth, Mary says, "Martin Luther King." "That's right Mary, you can go." Teacher: "Who said 'Ask not, what your country can do for you'?" Before Johnny can open his mouth, Nancy says, "John F. Kennedy." "That's right Nancy, you may also leave." The teacher turns her back, Johnny...