squaremeter = 1 * m**2 = sq_m
hectare = 10000 * m**2 = ha
squarekilometer = 1000000 * m**2 = sq_km
squarefoot = 0.09290341 * m**2 = sq_ft = squarefeet
squaremile = 2589988.110336 * m**2 = sq_mi
