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.
One acre equals 0.0015625 square miles, 4,840 square yards, 43,560 square feet or about 4,047 square metres (0.4047 hectares) (see below). While all modern variants of the acre contain 4,840 square yards, there are alternative definitions of a yard, so the exact size of an acre depends on which yard it is based.