A girl is observing a bird siting at a height of 500 in from the ground.The angle of elevation of the bird from the girl's eyes is 45° at the initial position.After some time,the girl moves on the ground towards the bird by 50 in and bird flies away from her At this point,the angle of elevation reduces to 30°.Find the distance travelled by the bird.Take "sqrt(3)=1.73"