(Solved): solve both problems , linear algebra Use a calculator to help you solve the problems. \( 1.5 \) poin ...

Use a calculator to help you solve the problems. \( 1.5 \) points \[ \text { Let } \mathbf{v}=\left[\begin{array}{c} 3 \\ 9 \\ -5 \\ 9 \\ 8 \end{array}\right] \text {. Find }\|\mathbf{v}\| \] Round your answer to two decimal places. \( 1.5 \) points For what value of \( k \) is \( \left[\begin{array}{l}k \\ 4 \\ 6\end{array}\right] \) orthogonal to \( \left[\begin{array}{c}-8 \\ 4 \\ 8\end{array}\right] ? \) Round your answer to two decimal places.