How to answer the following questions?Which of the following statements is a legal declaration/instantiation of a Stack object?A. StackInterface stack;B. StackInterface stack = new ArrayBoundedStack(3);C. StackInterface stack = new StackInterface;Evaluate the following postfix expression: 6 4 + 3 10 * 2 2 2 - + * + What is the highest number of elements on our stack at any one timeA. 2 B. 3 C. 4 D. 5While evaluating the following postfix expression: 6 4 + 3 10 * + 2 2 - + how many times is the push operation called? A. 1 B. 6 C. 9 D. 11 E. 18How did you decide to handle the possibility of stack underflow?A. Assume as a precondition that it will not occur.B. Throw a StackUnderflowException if it occurs.C. Provide an isEmpty operation so a client can prevent underflow.Ignore it.D. Throw a StackUnderflowException if it occurs, and provide an isEmpty operation so a client can prevent underflow. Here is a, possibly flawed, approach for using a traversal to print the contents of the linked list of strings accessed through letters. Indicate the description that best matches the code.LLNode currNode = letters;while (currNode != null) {System.out.println(currNode.getInfo());if (currNode.getLink() != null)currNode = currNode.getLink(); elsecurrNode = null;}A. very good B. correct but inefficient C. correct but too complex D. will bomb if list is empty E. will bomb if list is not empty What is the result of evaluating the following postfix expression? 6 4 + * 3 10 +A. 0 B. 3 C. too many operands D. too few operandsstack implementations throw an exception if a pop is attempted on an empty stack. A valid alternate approach to handling this situation is to:A. ignore it B. state as a precondition that pop will not be attempted on an empty stack.C. have the pop operation return a boolean indicating success. D state as a precondition that pop will not be attempted on an empty stack, and have the pop operation return a boolean indicating success. E. state as a precondition that pop will not be attempted on an empty stack, or have the pop operation return a boolean indicating success.which of these statements is the best representation of the current status of a Stack ADT in the Java Standard Library?A. There is no support for stacks in the library. B. The library provides a Stack class. C. The library does not provide a Stack class, but does provide other classes that can be used for the same functionality.D. The library provides a DeQue class that supports stack operations.E. The library provides a legacy Stack class, but it is better to use the DeQue class for stacks. the ArrayBoundedStack the topIndex variable holds the index of the elements array where the current top of stack is stored. Which of the following code sequences could be used to correctly remove the top element of the stack, assuming that pop is called on a non-empty stack?A. topIndex--; B. elements[topIndex] = null; C. elements[topIndex] = null; topIndex--;D. topIndex--; elements[topIndex]= = null;

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Stack is a ordered linear data structure which is used to store data.
The insertion…