Terra and enigmatic incarnation end step questions

Context: [[terra, magical adept]] backside creates copy of [[enigmatic incarnation]] that will be sacrificed next end step.

1. Will all three triggers be put on the stack at the same time so I can order them (two incarnation triggers resolve first and Terra sacrifice trigger last)?

2. If so, can I sacrifice the incarnations to each other to get two 5cmc creatures, or can I only sacrifice one of them?