For verifying characteristics compressive strength the M25 grade of concrete, which is the test done in the laboratory as per IS 456?
1
Compression test on 15 cm cubes at 28 days
2
Compression test on 10cm cubes at 28 days
3
Split test on 15 cm dia cylinder on 28 days
4
Compression test on 15 cm cubes at 7 days