Given data
The initial volume of the ballon is v = 2 L
The initial temperature is T = 20 C = 293 K
The ballon is placed inside the refrigerator at a temperator of T_f = - 18 C = 255 K
The pressure remains constant, the expression for the volume temperature relation is given as:
[tex]\frac{v}{T}=\frac{v_f}{T_{-f}}[/tex]Substitute the value in the above equation.
[tex]\begin{gathered} \frac{2\text{ L}}{293\text{ K}}=\frac{v_f}{255\text{ K}}_{} \\ v_f=1.740\text{ L} \end{gathered}[/tex]Thus, the final size of the ballon is 1.740 L.