Task: Question Answering
Input (English): Problem: two isosceles triangles have equal vertical angles and their areas are in the ratio 4 : 9 . find the ratio of their corresponding heights . 
Options: ['a ) 4 / 5', 'b ) 5 / 4', 'c ) 3 / 2', 'd ) 5 / 7', 'e ) 2 / 3']
Output (English): e