4. The reduced level of a floor is 99.995 m, the staff reading on the floor is 1.505 m. If the inverted staff reading against the roof is 1.795 m, the floor level below the slab, is
5. If F is the pull applied at the ends of tape in kg, l is the length of tape between end marks in metres, w is the weight of the tape in kg per metre run, then sag correction
6. If deflection angles are measured in a closed traverse, the difference between the sum of the right-hand and that of the left hand angles should be equal to