Solid system of laying underground cables has the drawback of

The system of laying underground cables adopted in congested areas, where excavation is expensive and inconvenient is

While laying 11 kV underground cable with the diameter D, the minimum bending radius must be

The depth of trench required for laying underground cables by direct laying method is

Underground cables are laid it sufficient depth so as to

Minimum distance of underground cables from the foundation of building should be

In case the communication cables are to be laid parallel to power cables, the distance between the two should be at least

While laying 33 kV underground cable with the diameter D, minimum bending radius should be

While crossing the road the cable should be

Consider the following statements
1.  The insulation resistance of cable will increase if the length of cable is increased
2.  For same overall diameter of cable, grading of cables will increase the safe working voltage
3.  The normal operating temperature of PVC cable is 70 °C
4.  The thermal resistance of soil increases as the moisture content of soil increases