What is the initial pressure of a gas having an initial temperature of 90.5 K, an initial volume of 40.3 L, a final pressure of 0.83 atm, a final temperature of 0.54 K and a final volume of 2.7 L?

EDIT: This pressure is moderate, but the temperature is quite low. So the gas is probably not very ideal. Nevertheless, the idea is probably to assume ideality anyway.
- Truong-Son