The self-cleansing velocity of water flowing through pipe lines, is___________________ ?
A. 2 metres/sec
B. 1 metre/sec
C. 0.5 metre/sec
D. 0.25 metre/sec
A. 2 metres/sec
B. 1 metre/sec
C. 0.5 metre/sec
D. 0.25 metre/sec