Consider the following vector function.

r$($t$)=($:$6$t$,(1)/(2)$t$^(2),$t$^(2)$:$)$

$($a$)$ Find the unit tangent and unit normal vectors T$($t$)$ and N$($t$).$

T$($t$)=$

N$($t$)=$

$($b$)$ Use this formula to find the curvature.

$\backslash$kappa $($t$)=$