Orthogonality & Least Squares · Medium problem

Apply Gram–Schmidt to $\mathbf v_1 = (1, 1, 0)$, $\mathbf v_2 = (1, 0, 1)$. The second orthogonal vector is $\mathbf w_2 = (a, b, c)$ with $c = 1$; find $a$ as a common fraction.