Răspuns :
[tex]\it x\in\mathbb{N},\ \ x+1<5|_{-1} \Rightarrow x<4 \Rightarrow A=\{0,\ \ 1,\ \ 2,\ \ 3\}\\ \\ 2^y<16\ \Rightarrow 2^y<2^4 \Rightarrow y<4\ \Rightarrow B=\{0,\ \ 1,\ \ 2,\ \ 3\}[/tex]
[tex]\it z\in\mathbb{N},\ z=y-1,\ y\in B \Rightarrow C=\{0,\ 1,\ 2\}\\ \\ A\cap B\cap C=\{0,\ \ 1,\ \ 2\}\\ \\ A-B=\varnothing;\ \ C-A = \varnothing; \ \ A-C=\{3\}[/tex]