"1. how many ancestors does a node at level n in a binary tree have? provide justification."

In binary tree there are n ancestor at level n.

Proof :

Take P(0): At node level 0, it has no ancestors since this is a roo tnode.

Take P(1): At node level 1, it has one ancestor. The ancestor is the root, its parents which is at level 0.

Take P(K): A node level K it has K ancestors. Its parent is at level K – 1.

Take P(K+1): At node K + 1 level have more than one ancestor than that of node at k level.

Thus there are n ancestor at level n in binary tree.

linear pair postulates

can you rephrase the question ? it is unclear : -)

step-by-step explanation: