This exercise is a multiple choice questionnaire. For each of the following questions, only one of the four proposed answers is correct.

A correct answer earns one point. An incorrect answer, a multiple answer or the absence of an answer to a question earns or loses no points.

Space is referred to an orthonormal reference frame $(\mathrm{O}; \vec{\imath}, \vec{\jmath}, \vec{k})$.

We consider:
\begin{itemize}
  \item The line $\mathscr{D}$ passing through the points $\mathrm{A}(1;1;-2)$ and $\mathrm{B}(-1;3;2)$.
  \item The line $\mathscr{D}'$ with parametric representation: $\left\{ \begin{aligned} x &= -4 + 3t \\ y &= 6 - 3t \\ z &= 8 - 6t \end{aligned} \right.$ with $t \in \mathbb{R}$.
  \item The plane $\mathscr{P}$ with Cartesian equation $x + my - 2z + 8 = 0$ where $m$ is a real number.
\end{itemize}

Question 1: Among the following points, which one belongs to the line $\mathscr{D}'$?\\
a. $\mathrm{M}_1(-1;3;-2)$\\
b. $\mathrm{M}_2(11;-9;-22)$\\
c. $\mathrm{M}_3(-7;9;2)$\\
d. $\mathrm{M}_4(-2;3;4)$

Question 2: A direction vector of the line $\mathscr{D}'$ is:\\
a. $\overrightarrow{u_1}\left(\begin{array}{c}-4\\6\\8\end{array}\right)$\\
b. $\overrightarrow{u_2}\left(\begin{array}{l}3\\3\\6\end{array}\right)$\\
c. $\overrightarrow{u_3}\left(\begin{array}{c}3\\-3\\-6\end{array}\right)$\\
d. $\overrightarrow{u_4}\left(\begin{array}{c}-1\\3\\2\end{array}\right)$

Question 3: The lines $\mathscr{D}$ and $\mathscr{D}'$ are:\\
a. intersecting\\
b. strictly parallel\\
c. non-coplanar\\
d. coincident

Question 4: The value of the real number $m$ for which the line $\mathscr{D}$ is parallel to the plane $\mathscr{P}$ is:\\
a. $m = -1$\\
b. $m = 1$\\
c. $m = 5$\\
d. $m = -2$