math

I don't really know what the question is, but I'm guessing that you want this speed expressed in miles per hour.

$\frac{1\text{ mile}}{0.5\text{ hours}}=\frac{1/0.5\text{ miles}}{0.5/0.5\text{ hours}}=\frac{2\text{ miles}}{1\text{ hour}}$

That speed is 2 miles per hour.

$\frac{1\text{ mile}}{0.5\text{ hours}}=\frac{2\text{ miles}}{1\text{ hour}}\times\frac{1,60934km}{mile}=3.21868km/hour$

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