A sample of helium gas occupies 1445 mL at 721 mmHg. For a gas sample at constant temperature, determine the volume of helium at 745 mmHg.

Is the He sample treated as an ideal gas? If yes, Boyle's law.

If not, it depends on how do you model the He sample (Van der Waals model being simple, Redlich–Kwong model sometimes more accurate, others more complicated, etc.).