I'm stuck please help me solve these question

Q-3: a) [6+4 marks] Let W = span{(1, 1, 0), (1, 0, 1), (2, 1, 1), (0, 1, -1) }. i. Is (9,0,9) in W? Justify your answer. ii. Is W = R3? Justify your answer. 1 2 W 1 3 3 b) [6+2+2 marks] Let A = 0 1 0 LO 1 2 0 i. Find the reduced row echelon form of A. ii. Find a basis for the subspace spanned by the rows of A. iii. Find a basis for the subspace spanned by the columns of A