The desired characteristic strength of a mix is 20 N/mm2. The standard deviation is 4 N/mm2 for 150 mm size of concrete cubes; and K = 1.645. The average strength of the cubes will be nearly

The desired characteristic strength of a mix is 20 N/mm2. The standard

1.	The desired characteristic strength of a mix is 20 N/mm2. The standard deviation is 4 N/mm2 for 150 mm size of concrete cubes; and K = 1.645. The average strength of the cubes will be nearly
A.	38.2 N/mm2
B.	32.4 N/mm2
C.	26.6 N/mm2
D.	22.8 N/mm2
Answer» D. 22.8 N/mm2