The angle of depression of the top and the foot of a chimney as seen from the top of a second chimney, which is 150 m high and standing on the same level as the first, are \( \theta \) and \( \phi \) respectively.
Then the distance between their tops when \( \tan \theta = \frac{4}{3} \) and \( \tan \phi = \frac{5}{2} \) is: