5. The compressive strength of an ordinary Portland cement (1 : 3 cement mortar cube) after 7 days test should not be less than
A. 22 N/mm2
B. 27.5 N/mm2
C. 11 N/mm2
D. 17.5 N/mm2
5. The compressive strength of an ordinary Portland cement (1 : 3 cement mortar cube) after 7 days test should not be less than
A. 22 N/mm2
B. 27.5 N/mm2
C. 11 N/mm2
D. 17.5 N/mm2