Let ${\bf a}_1 = \left[{\begin{matrix} 10 \cr 4 \cr \end{matrix}}\right]$, and ${\bf a}_2 = \left[{\begin{matrix} h \cr 2 \cr \end{matrix}}\right]$.

The set $\lbrace{{\bf a}_1, {\bf a}_2}\rbrace$ will span ${\mathbb R}^2$ unless $h=$.
(If there are no values of $h$ that make the set fail to span, enter "NONE". If the set fails to span for all values of $h$ enter "ALL".)