Dharma Questions: Miscellany — Part 5

This irregular “Dharma Questions” series deals with “dharma” meaning both the truth of the nature of reality and some Buddhist teachings. Amongst other things these questions can be:
• thought experiments
• borderline musings not meant to be answered
• from laziness of not contemplating or researching them yet

There’s 16 questions. Here’s two:

What is the root condition of annica — impermanence, inconstancy?

What are any and all similarities and differences between “Para Brahman” and “Nirvana”?