Step-by-step explanation:
To solve this question, we need to use the following formula:
PiVi = PfVf
Pi = initial pressure = 549 mmHg
Vi = initial volume = 449 mL
Pf = final pressure = 755.9 mmHg
Vf = final volume = ???
549*449 = 755.9*Vf
Vf = 326 mL
Answer: a. 326 mL