Answer: 3.815 x 10^15km
Explanation: The symbol is for micrometers. This is equal to 10^-6 meters. A meter is 10^-3 of a kilometer. Thus a micrometer is 10^-9 of a kilometer. So: 3.815 times 10^24 micrometers*(10^-9kilometers/micrometer)=3.815 x 10^(24-9)=3.815 x 10^15