Answer
$7.61\times10^2\ torr$
Work Step by Step
$P_{gas}=P_{atm}+12.3\ torr=(0.985\ atm\times\frac{760\ torr}{1\ atm})+12.3\ torr=760.9\ torr=7.61\times10^2\ torr$
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.