You are implementing a binary search tree class from scratch, which, in addition to insert, find, and delete, has a method getRandomNode() which returns a random node from the tree. All nodes should be equally likely to be chosen. Design and implement an algorithm for getRandomNode, and explain how you would implement the rest of the methods.

In Java,  Complete the incomplete method of ExpressionTree.java. The incomplete methods are private Node parsePrefix(Scanner input) // Required public void parseInfix(String string) // Optional public void parsePostfix(String string) // Optional Implementations of parseInfix and parsePostfix require use of a stack. Implementation of parsePrefix does not. Read all of the ExpressionTree.java file before starting your implementation, so that you see the helper methods that are provided and get an idea of the context for your implementation.  Although not needed for your implementation, you should be sure you understand how the toStringPrefix, toStringInfix, and toStringPostfix methods work. Note: The main() method accepts a single String as its argument. The String should be a prefix, infix, or postfix mathematical expression with no characters other than operators (+, -, *, and /) and operands (single characters a-z).  As written, the main() method calls parsePrefix() to create an…

Write a method isBST() that takes a Node as argument and returns true if the argument node is the root of a binary search tree, false otherwise.Hint : This task is also more difficult than it might seem, because the order in which youcall the methods in the previous three exercises is important

Please, use Java and write a clear answer to your own work and I'll rate up. Thank you :)