Answer:
42300000
Step-by-step explanation:
Use known fact
[tex]1\ km=1000\ m[/tex]
Consider 1 square kilometer:
[tex]1\ km^2=1\ km\times 1\ km=1000\ m\times 1000\ m=1000000\ m^2[/tex]
So, to find the answer, you have to multiply given number of square kilometers by 1000000:
[tex]42.3\ km^2=42.3\times 1000000\ m^2=42300000\ m^2[/tex]
