Pressure Cooker (压力锅) Safety When you arecooking with a pressure cooker, you should learn a few common sense (常识) rules: 1. Neverleave the cooker unwatched when it is in use. 2. Add sufficientliquid but never past the recommended fill point. Overfilling the cooker mayblock the vent pipe (排气孔) and cause the cooker to explode. 3. Set thecooking time. Too much time may overcook the food or too much pressure maybuild up in the cooker. Too little time will lead to undercooked food. 4. If you arenew to pressure cooking, follow the cooking instructions carefully Heat andtime can either result in a great meal or a ruined one. 5. Never tryto force a pressure cooker cover open. Allow the cooker to cool or run it undercool water before trying to open the cover. 6. Clean the cookerthoroughly after each use. Mild detergent (洗涤剂) and hotwater work the best. Do not use stove ash or sand for they may damage thecooker. The gasket (密封圈) is best cleaned in warm soapy water and then dried.Store the gasket in the bottom of the pot. 45. Which of the following operations may be dangerous?