Answer:
B) 54,000
Explanation:
[tex]\text{Average Spe}ed=\frac{Dis\tan ce}{Time}[/tex]Distance covered = 888,000,000 miles.
Time taken = 687 Earth-days.
We convert to hours.
[tex]\begin{gathered} 687Earth-days=687\times24 \\ =16,488\text{ hours} \end{gathered}[/tex]Thus, the average speed of Mars, in miles per hour is:
[tex]\begin{gathered} =\frac{888,000,000}{16,488} \\ =53857\text{ mph} \\ \approx54,000\text{mph (to the nearest thousand).} \end{gathered}[/tex]The correct choice is B.