\\9/ \\0/ \\4/ \\'1/ . Which of the following is the row-reduced echelon form of [ i :31 g ]? 1 O 5 1 2 1 1 0 1 1 0 6 Nollzl Malld Mall2] Molt] . Given the augmented matrix [ i g ' g ], which of the following is not a valid row operation? (a) Row 1> 2xRow 12XR0W 1 (c) Row 2 > Row 2 4XR0W 1 (b) Swap Row 1 and Row 2 ((1) Row 1 ) % Row 1 . Let P1, P2, P3 be three planes in R3 and let A be the augmented matrix corresponding to the three equations of these planes. Suppose that A has reduced row-echelon form: l l Which of the following could be a drawing of the intersections of the three planes P1, P2, P3? E E (a) E (b) (c) (d) 1 O 0 COM OOH DON)