1. in parts a and b, determine whether the set w is a subspace of r² with the standard operations. justify your answer. (a) w = {(x1,c2,4): x1 and 22 are real numbers } (6) w = {(s, t, s +t): s and t are real numbers} 2. determine whether the set of vectors p2 is linearly independent or linearly dependent. s = {-1+x²,5 + 2x} 3. determine whether the set s = {(5,6,5), (2,1, -5), (0, -4,1)} spans r. 4. determine whether s is basis for r. s = {0,0,0), (1,5,6), (6, 2, 1)}