Hello chegg expert please I need the correct and complete answers of those questions they are very important for me and in the same time it's urgent very very urgent please please help me I need your help

1-1. Which of the following cannot be solved by using the greedy algorithm? ( ) A. Exchange problem B. 4-Queen problem C. Huffman coding D. Overload problem 1-2. Which of the following is the best in average? ( ) A. Bubble sort B. Selection sort C. Insertion sort D. Quick sort 1-3. Which is the time complexity of binary search under the best case? ( ) A. Q(1) B. O(n) C. O(logn) D. O(nlogn) 1-4. The complexity of the formula T(n)=3nlogn+6n+1 is () A. O(3nlogn) B. O(6n) C. O(nlogn) D. O(1) 1-5. Matrix multiplication can be implemented by using? ( ) A. Dynamic Programming B. Greedy C. Backtracking D. Bound and Boundary