A 4.4 L cylinder containing helium gas at a pressure of 17.5 atm is connected to a 2.6 L cylinder containing helium at 3.5 atm. What is the final pressure when both the cylinders have achieved equilibrium?
a) 9.5 atm
b) 11.5 atm
c) 14.5 atm
d) 17.5 atm