#### Answer

$0.00000091$

#### Work Step by Step

Since the exponent of $10$ in the given expression, $
9.1\times10^{-7}
,$ is negative $7$, then move the decimal point $7$ places to the left. Hence, in standard form, the given expression is equivalent to
\begin{array}{l}\require{cancel}
0.00000091
.\end{array}