Find the sum of $20$ terms of the G.P., $0.15,0.015,0.0015................$

Question

$\begin{array}{1 1} \large\frac{1-(0.1)^{20}}{6} \\\large\frac{1-(0.1)^{20}}{60} \\ \large\frac{1-(0.1)^{20}}{3} \\ \large\frac{1-(0.1)^{20}}{30} \end{array} $