A pure substance has a boiling point of 80°C at 300 Torr and 120°C at 600 Torr. Which of the following statements is true for this substance?
(1) Its normal boiling point is below 80°C.
(2) Its normal boiling point is above 120°C.
(3) It is stable as a liquid at 80°C and 200 Torr.
(4) It is stable as a liquid at 200°C and 600 Torr.
(5) None of the above statements are true.