Problem Statement

Book Between Psychology and Sociology After Three Swaps Seven books, one each on Psychology, Hindi, English, Sociology, Economics, Education and Accountancy, are lying on a table one above the other. The following is known: I) Sociology is on the top of all the books. II) Accountancy is immediately below Education, which is immediately below Sociology. III) Economics is immediately above Psychology but is not in the middle. IV) Hindi is immediately below Psychology. If Sociology and English, Accountancy and Hindi, and Education and Psychology interchange their positions, then which book will be between Psychology and Sociology?