Answer
The common ratio is $r=10$.
Work Step by Step
The given sequence is
$0.1,1,10,100,...$
Calculate the ratio between each pair of consecutive terms.
$\frac{1}{0.1}=10$
$\frac{10}{1}=10$
$\frac{100}{10}=10$
Hence, the common ratio is $r=10$.
