Crushing strength of a first class brick should not be less than_____________?
A. 3.5 N/mm2
B. 7.0 N/mm2
C. 10.5 N/mm2
D. 14.0 N/mm2
A. 3.5 N/mm2
B. 7.0 N/mm2
C. 10.5 N/mm2
D. 14.0 N/mm2