Cuerda
A cuerda is a traditional unit of area used mainly in Puerto Rico to measure land.
1 cuerda ≈ 3,930 square meters ≈ 0.97 acres.
It is commonly used in real estate and agriculture on the island.
The cuerda remains a popular local measurement for land despite the use of metric units.
Circular Mil
A circular mil is a unit of area used mainly to measure the cross-sectional area of round wires and cables in electrical engineering.
Defined as the area of a circle with a diameter of 1 mil (1 mil = 0.001 inch).
Area = (diameter in mils)² circular mils.
1 circular mil ≈ 7.854 × 10⁻¹⁰ square meters or 0.7854 square mils.
Circular mils simplify calculations for round wires since area scales with the square of the diameter.