Find a theta notation for the best-case time required by the following algorithm: is_key(s, n, key) {for i = 1 to n - 1 for j = i + 1 to n if (si + sj =key) return 1 else return 0} Trace the algorithm of the Insertion Sort for the input 40 18 134 60 Algorithm: the insertion sort Input: s, n Output: s (sorted) insenion_sort(s. n) {for i = 2 to n {val = si//save si so it can be inserted into the correct placc j = i-l//if val