1)

a) 

Sequential (Linear) search:
2 5 8 12 16 23

b) 

Binary search:
Low    Mid    High
2      16      91
23     56      91
23     23      38

2) 

Sequential (Linear) search:
3 15 25 43

Binary search:
Low    Mid    High
3      50     120
3      15      43
25     25      43
43     43      43

3) 

Binary search:
Low    Mid    High
9      85     1000
9      23       78
9       9       15
15     15       15