1

2

1

-3

-1

(a)  

5

1

1

2

-1

(a)  

2

1

-2

5

-5

(a)  

5

4

-2

-1

-5

(a)  

20

2

-1

5

-1

(a)  

4

-2

30

1

5

(a)  

1

5

-5

40

-1

(a)  

4

50

-1

5

-3

(a)  

4

-2

-1

5

10

(a)  

23

1

-2

5

-1

(a)  

10

5

2

-1

10

(a)  

55

3

-2

3

-4

(a)  

20

10

50

-30

4

(a)  

2

30

1

5

-3

(a)  

41

2

5

-5

1

(a)  

22

-1

3

5

-20

(a)  

44

-1

1

5

-30

(a)  

25

1

2

-1

10

(a)  

11

5

2

-3

30

(a)