7. (4%) Which of the following statement(s) is (are) incorrect? (A) The maximum number of data items stored in an m-way search tree is mh1, where h is the height of the tree. (B) The minimum number of data elements is 2 in an B-tree. (C) An 2-3-4 tree is an B-tree of order 5. (D) Any internal node (excluding the root) has at least 2m children in an B-tree of order m. (A) (B) (C) (D) 8. (6\%) An Red-Black tree is initially empty. Now, 5 keys are inserted in the order of 3,7,4,9 and 1. Which of the following statement(s) is(are) true? (A) There are 6 external nodes. (B) It takes O(logn) time to insert a key into the Red-Black tree. (C) The node with key of 4 "may" be red. (D) It is possible that the path from the root to an external node traverses 2 red nodes, consecutively. (E) All paths from the root to any external node comprise of the identical number of black nodes. (A) (B) (C) (D) (E)