3x6

(a)  

2x7

(a)  

6x0

(a)  

12x1

(a)  

8x5

(a)  

7x3

(a)  

4x4

(a)  

10x7

(a)  

6x11

(a)  

7x9

(a)  

12x3

(a)  

6x2

(a)  

6x6

(a)  

9x10

(a)  

8x7

(a)  

9x4

(a)  

5x5

(a)  

0x1

(a)  

1x1

(a)