Respuesta :
[tex] \huge \underline \mathtt \colorbox{cyan}{20, 917, 008 kilometres}[/tex]
Or say, in scientific notation
[tex]2.0917008 \times 10^{7} km. [/tex]
Step-by-step explanation:
First convert, 3 weeks in hours{ezy} =504 hours
Now multiply with its speed.