The minimum compressive strength on 15 cm cubes of M 30 grade concrete at 7 days, should be a minimum of
A. 7 N/mm2
B. 10 N/mm2
C. 20 N/mm2
D. 30 N/mm2
Answer:C
The minimum compressive strength on 15 cm cubes of M 30 grade concrete at 7 days, should be a minimum of
A. 7 N/mm2 B. 10 N/mm2 C. 20 N/mm2 D. 30 N/mm2