This question evaluates understanding of heap data structures and the in-place bottom-up heapify algorithm for building a max-heap on a 0-indexed array, testing skills in array manipulation, heap invariants, and algorithmic reasoning.
Given the array [6, 15, 2, 4, 3, 8, 19], apply heapify to build a max-heap using the standard in-place bottom-up method with a 0-indexed array representation. What is the final array after heap construction? Show key steps or justify your result.