This problem focuses on the determination of homotopy groups.

(i) Let $M=\mathbb{R}^{3} \backslash\{$ a point $\}$. Find $\pi_{1}(M)$ and $\pi_{2}(M)$.

(ii) Let $M=\mathbb{R}^{3} \backslash\{$ a line $\}$. Compute $\pi_{1}(M)$.

(iii) Let $M=\mathbb{R}^{3} \backslash\left\{l_{1}, l_{2}\right\}$, where $l_{1} eq l_{2}$ are two parallel lines in $\mathbb{R}^{3}$. Determine $\pi_{1}(M)$.