Card 6
Turns/torus/tyres etc, based on f"'s answers and guessing the most likely results for t?r?s. Much less conclusive when I've read the clue properly. It looks like they may all be 5 letter words
Card 7
wiles Guessing that determin. means take the determinant, and that a=1,b=2..., the determinant of the matrix is 125239. There's various groupings that could work, but Lewi (12 5 23 9) is such that adding an "s" gives a name (lewis). Mixing that up gives you wiles.