There are two towers A and B. Their heights are 200ft and 150ft respectively and the foot of the towers are 250ft apart. Two birds on top of each tower fly down with the same speed and meet at the same instant on the ground to pick a grain. What is the distance between the foot of tower A and the grain?
1
120 ft
2
78 ft
3
100 ft
4
90 ft
5
150 ft.