8. Following code fragment is an optimized implementation of mergesort, answer following two questions: (1) What is the strategy of Mergesort and how to analyze its time complexity? (7 pts) (2) What does the function inssort() in the red rectangle refer to? Write out the detailed implementation of inssort(). (8 pts) template void mercesort (E AL. E tem 1. int left. int right) { if ((right-left) (&A (left), right-left+1); return; int i, j, k, mid = (left+right) 72; mergesort (A, temp, left, mid); mergesort (A, temp, mid+1, right); // Do the merge operation. First, copy 2 halves to temp. for (i=mid; i>=left; i--) temp[i] = A[i]; for (j=1; j