need help data structure question

(b) What's the factor by which a child node's problem instance size shrinks compared to its parent's problem instance size? (c) What's the height of mergesort3's recursion tree? (Indicate the base of any logs involved.) (d) How many nodes are there on layer of mergesort3's recursion tree (in the worst case)? (e) Approximately how many comparisons (including an estimate of the hidden big-O coefficient if possible) are performed by the natural merge3(A1,A2, A3) subroutine, as a function of its input size (i.e., n= len(A1)+len(A2)+len(AB)) in the worst case? (f) How much work is therefore done on layer of mergesort 3 's recursion tree? h) Draw the recursion tree, annotating it with your answers above