The Vector R(t) Is the Position Vector of a Particle $$\mathbf { r } ( \mathrm { t } ) = \sqrt { 3 } \mathrm { ti } + \left( \mathrm { t } + \frac { \pi } { 3 } \mathrm { t } ^ { 2 } \right) \mathbf { k }$$

Multiple Choice

The vector r(t) is the position vector of a particle at time t. Find the angle between the velocity and the acceleration vectors at time t = 0.
- $$\mathbf { r } ( \mathrm { t } ) = \sqrt { 3 } \mathrm { ti } + \left( \mathrm { t } + \frac { \pi } { 3 } \mathrm { t } ^ { 2 } \right) \mathbf { k }$$

A) $\frac { \pi } { 2 }$
B) 0
C) $\frac { \pi } { 3 }$
D) $\pi$