$1) P, V, T (\text{initial conditions}) \;\;\underrightarrow{\text{Isothermally}} \;\;2V, P_i, T$
$2) P, V, T (\text{initial conditions}) \;\;\underrightarrow{\text{Adiabatically}} \;\;2V_i, P_a,T$
Now, if $K_{gas} = \large\frac{P_a}{P_i}$, find $\large \frac{K_{H_2}}{K_{He}}$
(A) 1
(B) 1.2
(C) 0.83
(D) 1.44