A pressure cooker is a pot whose lid can be tightly sealed to prevent gas from entering or escaping. Even without knowing how big the pressure cooker is$,$ or what altitude it is being used at$,$ we can make predictions about how much force the lid will experience under different conditions.The pressure relief valve on the lid is now opened, allowing hot air to escape until the pressure inside the cooker becomes equal to the outside pressure papa. The pot is then sealed again and removed from the stove. Assume that when the cooker is removed from the stove, the air inside it is still at $120$C$.$

What is the magnitude of the net force F$20$ on the lid when the air inside the cooker has cooled back down to $20$C$?$