A solid steel ball of diameter \( 3.6 \, \text{mm} \) acquired terminal velocity \( 2.45 \times 10^{-2} \, \text{m}/s \) while falling under gravity through an oil of density \( 925 \, \text{kg m}^{-3} \). Take density of steel as \( 7825 \, \text{kg m}^{-3} \) and \( g \) as \( 9.8 \, \text{m/ s}^{2} \). The viscosity of the oil in SI unit is:
