500ca-1000dm berapakah jawabannya

1 ha=1hm^2

500ca-1000dm^2
(500:10000)hm^2-1000dm^2
0.05hm^2-1000dm^2
(0.05×10000)m^2-(1000:100)m^2
500m^2-10m^2=490m^2