If a binary tree has 25 nodes, how many null branches are there?

Clairvoyant replacement algorithm is also known as

What is the average time complexity of the median of three quicksort?

What is another name for the shell sort algorithm?

Which of the following methods is the most effective for picking the pivot element in a sorting algorithm like Quicksort?

A substitution-based cipher in which substitution is performed over a block of letters is called a:

What are the worst-case time complexities of insertion and deletion of a key in a binary search tree?

Compute the product matrix using Strassen's matrix multiplication algorithm.

Given:

a11 = 2, a12 = 4
a21 = 6, a22 = 8

b11 = 9, b12 = 5
b21 = 7, b22 = 3

An operator delete(i) for a binary heap data structure is to be designed to delete the item in the i-th node. Assume that the heap is implemented in an array and i refers to the i-th index of the array. If the heap tree has depth d (number of edges on the path from the root to the farthest leaf), then what is the time complexity to re-fix the heap efficiently after the removal of the element?