Problem: a math teacher has 27 cards , each of which is in the shape of a geometric figure . half of the cards are rectangles , and a third of the cards are rhombuses . if 8 cards are squares , what is the maximum possible number of cards that re circles . 
Options: ['a ) 9', 'b ) 10', 'c ) 11', 'd ) 12', 'e ) 13']
b