6 Two lines have equations
$$\mathbf { r } = \left( \begin{array} { r }
1
0
- 5
\end{array} \right) + t \left( \begin{array} { l }
2
3
4
\end{array} \right) \quad \text { and } \quad \mathbf { r } = \left( \begin{array} { r }
12
0
5
\end{array} \right) + s \left( \begin{array} { r }
1
- 4
- 2
\end{array} \right) .$$
- Show that the lines intersect.
- Find the angle between the lines.