A: we do not know.
We assume nothing is random, as every event is a direct causality of the information of the universe. "information" means "the way something is, in detail". so two balls hitting each other are doing so because they "were moving towards each other", or "information".
However, this assumes reality isn't quantized. "quantized" means "things can only be so small, once you get to that size, you can't have fractions of smaller forms of that number".
So, if reality was quantized, then two sets of information colliding could give a slightly different result then expected because of "missing numbers", just like when you try to multiply too large numbers of a cheap calculator.
OR, reality could suffers from influence by other dimentions, which could potentially be infinite, so everything is random (to a point).