3

1

4

(a)  

8

-6

7

(a)  

4

4

-7

(a)  

3

4

-6

(a)  

9

-5

4

(a)  

8

-6

4

(a)  

3

4

-5

(a)  

3

1

4

(a)  

2

4

3

(a)  

2

4

-1

(a)  

3

4

-5

(a)  

1

4

1

(a)  

4

4

-5

(a)  

3

4

-2

(a)  

7

-6

4

(a)  

2

-1

4

(a)  

8

-6

4

(a)  

2

4

1

(a)  

3

4

-5

(a)  

1

4

3

(a)  

4

4

-3

(a)  

4

-1

4

(a)  

6

-5

4

(a)  

3

-3

9

(a)  

8

-5

4

(a)  

1

3

4

(a)  

5

4

-8

(a)  

9

-8

6

(a)  

7

-6

4

(a)  

8

-7

4

(a)  

4

5

-6

(a)  

3

-1

4

(a)  

6

2

-5

(a)  

9

-7

6

(a)  

2

6

-7

(a)  

9

-8

4

(a)  

1

4

2

(a)  

9

-9

2

(a)  

4

4

-7

(a)  

10

4

4

(a)  

14

4

-5

(a)  

13

-2

4

(a)  

2

12

4

(a)  

3

4

12

(a)  

5

4

10

(a)  

2

11

4

(a)  

1

14

4

(a)  

2

14

-5

(a)  

3

4

11

(a)