Find the angle between the line \(q\)
and the plane \(\sigma \).
\[
\sigma \colon 2x-z+4 = 0;\qquad \qquad \begin{aligned}[t] q\colon x& = 5r, &
\\y & = -3+2r,
\\z & = -2;\ r\in \mathbb{R}
\\ \end{aligned}
\]
Round your answer to the nearest minute.
Given points \(C = [-2;3;-1]\),
\(D= [1;2;-3]\), find the angle
between the line \(CD\)
and the line \(p\).
\[
\begin{aligned}p\colon x& = 2 -s, &
\\y & = 3,
\\z & = 2s;\ s\in \mathbb{R}
\\ \end{aligned}
\]
Round your answer to the nearest minute.
Identify the real number \(x\)
which converts the numbers \(a_{1} = 3^{x-6}\),
\(a_{2} = 1\) and
\(a_{3} = 3^{x}\) into
three consecutive terms of a geometric series.