Area measurements

hectares	dimensions	area	acres
1 ha	100 m x 100 m	10,000 m 2	2.471 acres
100 ha	1 km x 1 km	1 km2	247 acres
10,000 ha	10 km x 10 km	100 km2	24,710 acres
1,000,000 ha	100 km x 100 km	10,000 km2	2,471,000 acres
100 million ha	1000 km x 1000 km	1 million km2	24.71 million acres

Also:
1 acre= 4,047 square meters
1 square mile = 640 acres = 2.590 square kilometers = 259 ha

 

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