Trees - General Questions

What is the maximum number of nodes in a binary tree of height 10 (a single node has height 1)?

What is the maximum number of nodes at level 6 of a binary tree (root at level 0)?

What is the minimum possible height of a binary tree with 49 nodes (a single node has height 1)?

What is the minimum possible height of a binary tree with 74 nodes (a single node has height 1)?

A full binary tree (every node has 0 or 2 children) has 49 internal nodes. How many leaves does it have?