Answer
$\frac{1}{10^6}$
Work Step by Step
To raise a power to a power, multiply the exponents.
$(10^3)^{-2}\longrightarrow$ to raise a power to a power, multiply the exponents
$=10^{-6}\longrightarrow$ express the result using a positive exponent
$=\frac{1}{10^6}$