Yes, you have, and yes, it is (see also below to get straight to the point and to the relevant reference).
Yes, you could.
Looks like I’ve done it for you, though:
.
See also some other posts linked above.
I’ve got no time for the rest of the topic now — sorry if I’ve missed something substantial, although it’s probably… the usual 
, but I suppose I’ve answered definitively regarding the subject proper, which is why I stopped by here in the first place, and that’ll do for now.
PS Oh, come to think of it, one more thing: I don’t think they’ve ever actually promised that ‘random’ effects are ‘truly’ random, that they have equal or appropriately weighted odds (e.g. that Ragnaros can hit all targets with equal probabilities) — it’s mostly something the players would assume, but it’s not written anywhere officially, AFAIK. Someone made a topic (can’t be bothered to look it up now, sorry) about how improbable events seem very much more probable in HS, possibly in order to make it more ‘exciting’ — I’d even go ahead and assume that, say, 5% events have the probability of 95% to happen in HS 
, it’s not something I haven’t observed over the years. Well, but this postscriptum is getting longer than the post itself, so I suppose I’ll stop here… for now.