2. Let W be the subspace of R^5 spanned by the vectors w_1 = (2, 2, -1, 0, 1), w_2 = (-1, -1, 2, -3, 1), w_3 = (1, 1, -2, 0, -1), w_4 = (0, 0, 1, 1, 1). Find a basis for the orthogonal complement of W.