the volume, in liters, occupied by 45.0 g of Ar gas.

Answer 1

The volume will depend on the temperature and the pressure. If it is at STP , simply convert 45 g of Ar to moles by using the atomic mass of Ar and then use the fact that each mole occupies 22.4 liters at STP.

If the conditions are other than STP, you’ll need to state them.