Solution
= Solution
The <vector> $\mathbf c=\mathbf p\times\hat{\mathbf a}$ is a <normal vector> to the span of $\mathbf p$ and $\hat{\mathbf a}$. Since $\mathbf c\ne0$, these <vectors> determine a <plane>. Thus the missing words are
\b[the line and the origin].
Indeed this <plane> consists of all <linear combinations> of $\mathbf p$ and the line's direction <vector>.