6

4

4

1

-3

3

4

(a)  

1

9

-8

6

2

8

7

(a)  

3

9

8

1

4

5

7

(a)  

7

4

9

8

2

5

-2

(a)  

8

7

-4

3

5

2

-3

(a)  

9

7

4

3

2

3

7

(a)  

7

3

4

9

2

2

2

(a)  

1

8

8

5

-9

6

-2

(a)  

8

4

9

9

2

7

3

(a)  

76

22

-43

(a)  

12

76

-24

32

(a)  

73

84

-37

-40

(a)  

63

12

-25

45

(a)  

41

52

32

-42

(a)  

12

32

65

-24

(a)  

64

56

21

-65

(a)  

36

36

35

-53

(a)  

95

57

62

-84

(a)  

50

45

-92

91

(a)