Question 1 . which of the statements below is not true? a. a linear independent set of vectors in r" can be expanded into a basis for r by adding, if needed, some vectors from the standard basis for r. the row space of a matrix a is a set of all linear combinations of rows of a. the row space of an m × n matrix a is a subspace of rn if two matrices a and b are row equivalent, then their row spaces are the same. a basis for row a is the set of rows in a which correspond to the nonzero rows in an echelon b of a. b. c. d. e.