Sets And Relations

If $\mathrm{A}=\left\{\mathrm{x}: \mathrm{x}\right.$ is an integer and $\left.\mathrm{x}^2-9=0\right\}$

$B=\{x: x$ is a natural number and $2 \leq x<5\}$

$\mathrm{C}=\{\mathrm{x}: \mathrm{x}$ is a prime number $\leq 4\}$

Then $(B-C) \cup A$ is,