Question

QUESTION 7 10.00000 points Save Answer It is good levelling field work practice to keep the lenghts of Back Sights and Fore sights at each set up equal because instrument errors are proportional to distance so will cancel out when the lenghts are equa Othe staff readings will be similar, so errors due to poor connections in the leaves of the staff will be eliminated. O levelling field work is speeded up because the telescope focus will be the same for each sight O it makes it easier for the person holding the staff to find a new location Oif the line of sight gets too close to the ground it will be refracted by heat from the footpaths on hot days QUESTION 8 A Reduced Level is Othe height of a point above or below a known datum. 10.00000 points Save Answer the height of a point reduced by a scale factor to compensate for its position within Australia O a little surveying instrument used where the lengths of sight are short Ofound when the first staff reading on a levelling job is made. none of the above

Answer 1

(a) instrument errors are proportional to distance so will cancel out when lengths are equal (a)height of a point above or below a known datum.