Find the Indicated Vector $\mathbf { a } = 3 \mathbf { i } , \mathbf { b } = \mathbf { i } + \mathbf { j }$

Multiple Choice

Find the indicated vector.
-Let $\mathbf { a } = 3 \mathbf { i } , \mathbf { b } = \mathbf { i } + \mathbf { j }$ . Find $3 \mathbf { a } + \mathbf { b }$ .

A) $\mathbf { i } + 10 \mathbf { j }$
B) $10 \mathbf { i } + 3 \mathbf { j }$
C) $11 \mathrm { i } + \mathbf { j }$
D) $10 \mathbf { i } + \mathbf { j }$