Let B be a \((4\times3)(4\times3)\) matrix in reduced echelon form.

a) If B has three nonzero rows, then determine the form of B.

b) Suppose that a system of 4 linear equations in 2 unknowns has augmented matrix A, where A is a \((4\times3)(4\times3)\) matrix row equivalent to B.

Demonstrate that the system of equations is inconsistent.