How do I add 35?
How do I know whether to move a key up(up to the node with 34 and 78, and if I do that, which key do I move up) and make more children(to fulfill the "A non-leaf node with k children contains k−1 keys." rule)
OR
just split up the 39,44,56,74(and 35) node into three children, like what I did in step 8.