For each of the following pairs, choose the substance with the higher entropy per mole at a given temperature:
(a) Ar(l) or Ar(g)
(b) He(g) at 3 atm pressure or He(g) at 1.5 atm pressure,
(c) 1 mol of Ne(g) in 15.0 L or 1 mol of Ne(g) in 1.50 L,
(d) CO2(g) or CO2(s).