5. The lime which contains more than 30% of clayey impurities in the form of silica, alumina and iron oxide, is known as
A. limestone
B. hydraulic lime
C. rich lime
D. poor lime
5. The lime which contains more than 30% of clayey impurities in the form of silica, alumina and iron oxide, is known as
A. limestone
B. hydraulic lime
C. rich lime
D. poor lime