Answer: 444 mmhg
Explanation: to do this problem you need to use the p1v1=p2v2 formula, which is boyle's law.
plug in the values into the equation -> (12)(740)=(20)p2
expand -> 8880=(20)p2
8880/20=p2
444=p2
444 mmhg is the new pressure
if they are asking for pressure in atm make sure to convert mmhg into atm before plugging into the equation!