AD = 100m and AB = 10m
The coordinates of Niharika's flag = (2, 25) and the coordinates of Preet's flag = (8, 20).
A(2, 25) and B(8, 20)
AB = √(20 - 25)² + (8 - 2)² = √(-5)² + 6² = √25 + 36 = √61
Distance between both flags is √61m.
Rashmi has to place her flag at the midpoint of AB.
MIdpoint of AB = ((2 + 8)/2, (25 + 20)/2) = (5, 22.5)
Rashmi must place her flag along the fifth line at 22.5m from A.