Answer
$231,000 \frac{km}{s}$, which is about 77 percent of the modern value.
Work Step by Step
$$v = \frac{300,000,000 \; km}{1300 s} = 231,000 \frac{km}{s}$$
$$ \frac{231000 km/s}{300000 km/s} = 0.77$$
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