Cement, or Portland cement, is a dry powder made. from limestone and other materials. It is burned in a. kiln and then finely ground. Cement reacts chemically. with water to cause concrete to harden.
There are 43,560 square feet in a acre; this is 4,840 square yards. You can find a conversion calculator at http://www.unitconversion.org/area/acres-to-square-foots-conversion.html Originally, the size of an acre was approximately the amount of land an ox could plow in a day.here are 43,560 square feet in a acre; this is 4,840 square yards. You can find a conversion calculator at http://www.unitconversion.org/area/acres-to-square-foots-conversion.html Originally, the size of an acre was approximately the amount of land an ox could plow in a day.
You can do the reverse unit conversion from square feet to acre, or enter any two units below: I'm feeling lucky, show me some random units. An acre is a measure of land area in Imperial units or U.S. customary units. It is equal to 43 560 square feet, 4840 square yards, or 160 square rods. The precise meaning of this depends on the exact definition adopted for a foot: the international acre is 4 046.856 422 4 m (for the UK, see). For measurements based specifically on the US survey foot the US survey acre is ca. 4 046.872 610 m.