Find the Length of the Plane Curve Given Below $\mathbf { r } ( t ) = 3 \cos t \mathbf { i } + 3 \sin t \mathbf { j } , [ 0,6 ]$

Multiple Choice

Find the length of the plane curve given below. $\mathbf { r } ( t ) = 3 \cos t \mathbf { i } + 3 \sin t \mathbf { j } , [ 0,6 ]$

A) 20
B) 9
C) 17
D) 19
E) 18