6. While measuring the distance between two points along upgrade with the help of a 20 m chain, the forward end of the chain is shifted forward through a distance
9. To orient a plane table at a point P roughly south of the mid-point of two inaccessible conical hill stations A and B in the plains, a point C is selected in line with AB and table is oriented at C by bringing ab in line with AB. A ray is then drawn towards P and at P the table is oriented by back ray method. The orientation so obtained, is
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