Consider one mole of helium gas enclosed in a container at initial pressure p1 and volume V1. It expands isothermally to volume 4V1. After this, the gas expands adiabatically and its volume becomes 32V1. The work done by the gas during isothermal Wiso and Wadia adiabatic expansion processes are and , respectively. If the ratio \(\frac{W_{iso}}{W_{adia}}\) = f In2, then f is ........-