Task: Question Answering
Input (English): Problem: the ratio between the radii of two spheres is 1 : 3 . find the ratio between their volumes ? 
Options: ['a ) 1 : 28', 'b ) 1 : 27', 'c ) 1 : 29', 'd ) 1 : 39', 'e ) 1 : 22']
Output (English): b