Task: Question Answering
Input (English): Problem: perimeter of an equilateral and isosceles is 45 and 40 respectively . at least one of the sides of isosceles is equal to the equilateral . what ' s the base of isosceles triangle ? 
Options: ['a ) 7', 'b ) 8', 'c ) 9', 'd ) 10', 'e ) 11']
Output (English): d