[填空题]
What is the approximate pressure inside a pressure cooker if b3ye6or py3.ktpqt +s.v5m0 tthe water+ o(:5qyomht 3tkh .7m s1omef is boiling at(tho em5:fs .m +73tqyo1mkho a temperature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C. atm