A. Mean radius of sewer B. Difference in heads between two points in circular pipes C. Mean of radii in a pipe line of varying cross -sections D. Cross-sectional area/wetted perimeter
A. Both a and r are true and r is the correct explanation of a B. Both a and r are true but r is not a correct explanation of a C. A is true but r is false D. A is false but r is true
