Determine the Values of C Such That $\| c u \| = 9$

Multiple Choice

Determine the values of c such that $\| c u \| = 9$ ,where $\mathbf { u } = \mathbf { i } + 8 \mathbf { j } + 9 \mathbf { k }$ .

A) $\pm 10 \sqrt { 146 }$
B) $\frac { 9 } { 146 }$
C) $\pm \frac { 10 \sqrt { 146 } } { 146 }$
D) $- \frac { 9 } { 146 }$
E) $\pm \frac { 9 \sqrt { 146 } } { 146 }$