Answer
1.25 cubic meters
Work Step by Step
Use the ideal gas model. The amount of gas, n, is constant. The value of PV/T remains constant.
$$\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}$$
$$V_2=V_1\frac{P_1}{P_2}\frac{T_2}{T_1}$$
$$V_2=(3.50m^3)\frac{1.00atm}{3.20atm}\frac{(273+38.0K)}{273K}=1.25m^3$$