Vectors Practice Test

Let $$\vec{v} = \langle -3, 6 \rangle$$ and $$\vec{w} = \langle 2, 4 \rangle$$. What is the dot product $$\vec{v} \cdot \vec{w}$$?

Let $$\vec{a} = \langle 2, 2 \rangle$$ and $$\vec{b} = \langle 0, 3 \rangle$$. What is the measure of the angle $$\theta$$, in radians, between vectors $$\vec{a}$$ and $$\vec{b}$$?