Regardless of what you chose in $2\mathrm{.}3,$ answer this question based on the fact that the nullspace is span$\{([0],[1],[-1])\}$ In this case, the nullspace is: A line in $R^3$ A plane in $R^3$ A vector in $R^3$ A line in $R^2$ A plane in $R^2$ A vector in $R^2$ None of these