A. additional B. ideally C. altered D. personal E. likely F. excessive G. virtually H. combined I. exceed J. errors K. preferably L. exist M. motion N. operation O. while In a telephone survey of more than 2,000 adults, 21% said they believed the sun revolved around the earth. An 17% did not know which revolved around which. I have no doubt that 2 all of these people were taught in school that the earth revolves around the sun; they may even have written it on a test. But they never 3 their incorrect mental models of planetary 4 because their everyday observations didn't support what their teachers told them: People see the sun moving across the sky as morning turns to night, and the earth seems stationary 5 that is happening. Students can learn the right answers by heart in class, and yet never 6 them with their working models of the world. The objectively correct answer the professor accepts and the student's personal understanding of the world can 7 side by side, each unaffected by the other. Outside of class, the student continues to use the 8 model because it has always worked well in that circumstance. Unless professors address specific 9 in students' personal models of the world, students are not 10 to replace them with the correct ones.