Vessels 1 and 2 contain v = 1.2 moles of gaseous helium. The ratio of the vessels'

Question:

Vessels 1 and 2 contain v = 1.2 moles of gaseous helium. The ratio of the vessels' volumes V2/V1 = a = 2.0, and the ratio of the absolute temperatures of helium in them T1/T2 = β = t.5.
Assuming the gas to be ideal, find the difference of gas entropies in these vessels, S2- S1.