An economical cross-section of an irrgation canal is formed partly in cutting and partly in filling, with the depth of cutting in canal cross-section equal to balancing depth. What does this indicate ?
1
Quanty of earthwork in cutting = Quantity of earthwork in filling
2
Quantity of earthwork in filling = Two times the quantity of earthwork in cutting
3
Wetted perimeter of cutting portion of canal = Wetter perimeter of the filling portion of canal
4
Depth of earthwork cutting = Depth of earthwork in filling