**Question:**

Let $\mathrm{N}$ denote the set of all natural numbers. Define two binary relations on $N$ as $R_{1}=\{(x, y) \in N \times N: 2 x+y=10\}$ and $R_{2}=\{(x, y) \in N \times N: x+2 y=10\}$. Then

Correct Option: 3

**Solution:**

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