Let $\mathbf { a } ( t ) = - 9.5 \mathbf { k }$

Multiple Choice

Let $\mathbf { a } ( t ) = - 9.5 \mathbf { k }$ be the acceleration of an object with velocity $\mathbf { v } ( t )$ . If $\mathbf { v } ( 0 ) = 2 \mathbf { i } - 3 \mathbf { k }$ then the speed $\| \mathbf { v } ( t ) \|$ is

A) $\sqrt { ( 9.5 t + 3 ) ^ { 2 } - 4 }$
B) $\sqrt { ( 9.5 t + 3 ) ^ { 2 } + 4 }$
C) $\sqrt { 90.25 t ^ { 2 } + 13 }$
D) $\sqrt { 90.25 t ^ { 2 } + 5 }$
E) $\sqrt { ( 9.5 t + 3 ) ^ { 2 } + 25 }$