Question d’entretien chez Microsoft

[Technical] 1. What is a binary tree? 2. What is a binary search tree? 3. Write an algorithm to find and return the node in a binary search tree with the nearest value larger than the input value. (So if the tree had nodes with values 1, 2, 4, 5, and 7 and the input value were 4, return the node with the value of 5.)