Read the directions carefully and answer the following questions. Seven persons O, P, Q, R, S, T, and U live in six floored building but not necessarily in the same order. The ground floor is numbered 1, and the topmost floor is numbered 6. P lives on an even numbered floor above the fourth floor. Two persons live between P and Q. Three persons live between Q and R. More than four persons live between R and S. T lives just above U. How many persons live between P and Q?