Searching - General Questions

Linear search is preferable to binary search when:

Using binary search (mid = ⌊(low + high)/2⌋) on the sorted array [2, 7, 11, 15, 17, 19, 20, 31], how many comparisons with array elements are needed to find 17?

Using binary search (mid = ⌊(low + high)/2⌋) on the sorted array [2, 7, 8, 14, 15, 17, 26, 27, 31, 39, 43, 47, 51, 55, 59], how many comparisons with array elements are needed to find 8?

Binary search on n sorted elements runs in:

Using binary search (mid = ⌊(low + high)/2⌋) on the sorted array [3, 5, 11, 19, 23, 27, 32, 35, 39], how many comparisons with array elements are needed to find 39?