EXERCISE

$(1)$

A site for a new road across a filled up valley has been prepared and centre line pegs at $50m$ intervals have been levelled and indicate a slope of one in a hundred $(1$:$100).$ The first and last stations, chainage $0m$ and $500m$ are on bed rock, but it is feared that subsidence had taken place in between and the cuttings were relevelled. From the following data, determine the reduced level of the pegs and indicate whether there has been any subsidence and if so how much. Assume the height of the bench mark is $10,000m$

$\backslash$table$[[$INSTRUMENTATION$,$STAFF READINGS $($NUMBERS IN BRACKETS INDICATE$],[$CHAINAGE OF PEGS$),,,],[,$ bench mark$),2,120(0m),1,625(50m)$