Exam of each of P, Q, R, S, T, U and V is on a different day of a week starting from Monday and ending on Sunday. P's exam is on Tuesday. Q's exam is on the day immediately after U's exam. Only three persons have their exam between the exam of U and T. V's exam is immediately after Q's exam. Only two persons have their exam between the exam of P and U. R's exam is not on Thursday. On what day is S's exam?