a. (10 points) Construct a BST by inserting the following keys into an empty BST, in order. 15,17,10,2,19,18,14,8,7,16,3,4,11. b. (5 points) Delete the node with value 15 from the resulting BST tree in part "a." by copying. c. (5 points) Delete the node with value 15 from the resulting BST tree in part "a." by merging..