Answer:
2 000 000 [tex]cm^{2}[/tex]
Step-by-step explanation:
100 [tex]km^{2}[/tex] = 1 000 000 000 000 [tex]cm^{2}[/tex]
the scale of 1:500000 means that 1 cm in the map represents 500000 cm in reality
So on the map this pond's area would be
[tex]\frac{1 000 000 000 000}{500000}[/tex] = 2 000 000 [tex]cm^{2}[/tex]