A square hectometer (often abbreviated as hm²) is a unit of area in the International System of Units (SI). It represents a square with sides that each measure 100 meters (10,000 centimeters) in length.
One square hectometer is equal to 10,000 square meters (m²) because each side of the square is 100 meters long, and when you square that length, you get 10,000 square meters.
To put it in perspective, a square hectometer is equivalent to 0.01 square kilometers (km²) because 1 square kilometer is equal to 100 hectares.
Square hectometers are not as commonly used as some other units of area, but they can be helpful for measuring large land areas, especially in some scientific and land management contexts.
The "square foot (US survey)" is a unit of area used in the United States primarily for land surveying and mapping purposes. It differs from the standard square foot because it is based on the U.S. survey foot, which is a historical unit of length used in land surveying in the United States. The U.S. survey foot is slightly different from the international foot.
One square foot (US survey) is equal to approximately 0.0929034119223 square meters (m²) or about 0.111111 square yards (yd²).
This unit is used in various land-related applications, particularly in the United States, where the U.S. survey foot and the square foot (US survey) are still employed for legal and historical reasons in certain land surveys and property descriptions. It's essential to be aware of the specific units being used when dealing with land measurements to avoid any discrepancies or errors.