Direction: Study the following information carefully and answer the questions given below.

Eight persons are sitting around two concentric circles. Ava, Ben, Charlie, and Dev are sitting in the inner circle while Mary, Nick, Oliver, and Paul are sitting in the outer circle. The persons sitting in the outer circle are facing towards the center while the persons sitting in the inner circle are facing away from the center. They solved a different number of questions viz. 42, 54, 59, 81, 85, 97, 101 and 169.

Ben is facing the west direction but is not facing towards the center. Dev has solved the second-lowest number of questions. The number of questions solved by the person, who is facing north direction is a perfect square and is facing towards the center. The difference between the number of questions solved by Ava and Dev is the same as the difference between the number of questions solved by Ben and Charlie. The number of questions solved by Charlie is a multiple of 5 and is facing north. Ben faces Oliver and the difference between the number of questions solved by them is four, where Oliver solved a greater number of questions. Paul faces the person, who solved the least number of questions. Only one person sits between the person, who solved 169 questions and the person who solved a perfect square number of questions. Mary is facing north direction and is sitting to the immediate left of Paul and both are facing towards the center.  Charlie faces the person, who solved the highest number of questions.