[tex]1m=100cm\\1h=3600s\\\\-----------------------------\\\\3.2\times10^{-4}\ m/h=3.2\times10^{-4}\times\frac{100cm}{3600s}=3.2\times10^{-4}\times\frac{1}{36}\ cm/s\\\\\approx0.08888...\times10^{-4}\ cm/s=8.889\times10^{-6}\ cm/s\\\\Answer:\fbox{A.}[/tex]