Answer:
the norm of V = =11.357816691601..
Step-by-step explanation:
[tex]\left\vert \overrightarrow{V} \right\vert =\sqrt{\left( -8\right)^{2} +\left( 7\right)^{2} +\left( 4\right)^{2} }[/tex]
[tex]=\sqrt{64+49+16}[/tex]
[tex]=\sqrt{129}[/tex]
[tex]=11.357816691601...[/tex]