In a falling head permeameter, a soil sample 75 mm in diameter and 36mm in length was tested. At the commencement of the test, the initial head was 80 cm and after one hour, the head drops to 40 cm. The coefficient of permeability if the diameter of the stand pipe is 1 cm, in cm/sec will be:
A1.98 x 10^-3
B1.88 x 10^-3
C1.98 x 10^-2
D1.23 x 10^-5