Why not, added.
In "przyroda" I do not hear the second R.
Is it normal? I hear it like "przyoda"
It's not normal, silent letters in Polish are very rare. But I agree. I hear something between "przyoda" and "przyhoda" (not exactly a Polish 'h'). Anyway, I disabled the audio exercises for this phrase.
What is the difference between "przyroda" and "natura"? This may have been asked in another lesson -- if so, I apologize.
I found an explanation from Alik here: https://forum.duolingo.com/comment/35925213