34) What is the postion of line of collimation, if observed staff reading is more than the required true staff reading?

35) What is the position of line of collimation While the observed reading is the less than the required true reading?

36) What is the diameter of earth?

37) What is the curvature of earth correction?

38) Which level is that the line of sight remains horizontal once the operator has roughly levelled the instruments?