a) Wyniki doświadczenia losowego możemy przedstawić graficznie za pomocą drzewa:

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b)

$A=\left\{\left(1,4,O\right),\left(4,1,O\right),\left(1,4,R\right),\left(4,1,R\right),\left(2,3,O\right),\left(3,2,O\right),\left(2,3,R\right),\left(3,2,R\right)\right\}$  

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$B=\left\{\left(2,2,R\right),\left(2,3,R\right),\left(3,2,R\right),\left(3,3,R\right),\left(2,5,R\right),\left(5,2,R\right),\left(5,3,R\right),\left(3,5,R\right),\left(5,5,R\right)\right\}$  

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$C=\left\{\left(1,1,O\right),\left(1,1,R\right),\left(1,2,O\right),\left(1,2,R\right),\left(2,1,O\right),\left(2,1,R\right),\left(1,3,O\right),\left(1,3,R\right),\left(3,1,O\right),\left(3,1,R\right),\left(1,4,O\right),\left(1,4,R\right),\left(4,1,O\right),\left(4,1,R\right),\left(1,5,O\right),\left(1,5,R\right),\left(5,1,O\right),\left(5,1,R\right)\right\}$