The Magnitude of the Acceleration of a Particle Moving Along $\mathbf { r } ( t ) = \sin ( 4 t ) \mathbf { i } - \cos ( 4 t ) \mathbf { j } + 7 \mathbf { k }$

Multiple Choice

The magnitude of the acceleration of a particle moving along the curve $\mathbf { r } ( t ) = \sin ( 4 t ) \mathbf { i } - \cos ( 4 t ) \mathbf { j } + 7 \mathbf { k }$ is

A) $2 \sqrt { 2 }$
B) 16
C) $4 \sqrt { 2 }$
D) $\sqrt { 5 }$
E) $9 \sqrt { 2 }$